I seem sure of what exactly? The word "Allah" meaning "The God" can refer to anything, just like "The Truck" can be a nickname for practically anyone or anything as well, but so can Jesus (which has a meaning as well and can refer to any number of people, concepts, or whatever else).
So what you seem sure of is that you know some name of God? You think God has a name? So you not only believe God has a name, but also that the name of God is some specific thing, and that the specific thing you think is God's proper name can't be used to refer to any number of ideas, concepts, individuals, entities, or whatever else? The whole implication is absurd.
Firstly, you have to establish for us and our atheist friends here what is God or a god anyway? Then you have to make it so that whatever that thing is you are talking about as a god has some match up to something that is considered or can be established as real. Then, you have to go further to make it clear how this thing you are talking about has communicated to you and made you certain that there is a proper name for it that should be used exclusively, and like a phone number, no other prayer or plea reaches this God unless its proper calling card is used (which is also not traditionally allowed for YHWH, they call YHWH Adonai and pronounce it Adonai, which simply means Lord, as they are not allowed to utter God's name generally).
You won't likely be able to do any of that, so all you're left doing is bothering this person who prefers calling God "Allah" and saying that "Allah is Real, a Real God"? Why do you want to bother this person? Its probably because you don't like the word Allah, you don't like Muslims or what you have seen and heard of them in the world and on the television and whatever, and you think that Allah is "too vague" somehow by meaning "The God" or "God" (though its unlikely you've complained about other people saying "God" in general and not questioning them about it in a snakey sort of fashion, almost like a bigot), so I'd prefer if you could just come out and be real with people on here and not so passive and cowardly seeming, and come outright and say that you think the word Allah is a bad one to use, that you object to it and would never use it yourself because you think its wrong, or evil, or could refer to anything, even though the Bible uses the terms Elohim and El and Eloah and Illah and all sorts of things, and in the Arabic and other translations uses the word Allah as well throughout, but you don't like it probably right, because you think Muslims are rotten, right?
Well, I'm a stronger and bolder person than you seem to be, so let me pave the way for you by saying that I don't like the Muslims on TV either, and I don't think they are all referring to the same Allah, just like I don't think all people who say God are referring to the same God, and before you get too excited, I don't think everyone who uses the word YHWH or JESUS is referring to the same YHWH and JESUS either, but everyone is carrying in their minds their own ideas and concepts and references. Furthermore, according to the Bible and more clearly the Qur'an, there simply IS NOT OTHER GOD OR ENTITY IN EXISTENCE LIKE GOD, so if one says "The God" it only refers to the Real God that the Qur'an claims is the only one that exists, and going further, The God of the Qur'an encompasses all the other Gods and their powers, as there is only one. So Allah is all of them and One, Allah is the one controlling rain or fire or thunder etc, so Allah is the true Tlaloc, Agni, or Thor, and there is no other according to the Qur'an. Read it for yourself here at
www.islamawakened.com/quran .
So what is confusing about that unless you are deliberately trying to make trouble for people and give them a hard time over nothing? YHWH "I am that I am" "I am what I will be" or any translation of it, is much more confusing and meaningless and absurd and wild and even silly to say in a sentence and awkward than it is to say "There is only one God, The God, The One God, there is no Other God but The God, The One God, The is the Definite Article, THE, there is no other, its THE ONE" that is the whole concept of the Qur'an regarding God, so there simply is no other that people can even refer to if they are referring to whatever at all is Ultimate.
Its the way you approached this person, the way you went at them for their statement and bothered them, the way you seem to be concealing your dislike for the term or word Allah, the way you put all these peace symbols around you yet you bother people like that, makes you seem like a sort of snake-like and malicious entity. You have a chance though, to shed your snake-like skin and instead be overt about your feelings and motivations and reveal and expose yourself and just come outright and say that you think Allah is a bad word, an evil name, for an evil false God, if that is what you want to say.
You probably hate Allah as a word more than any other word. Shiva means Auspicious, who do you think that Shiva is according to the Qur'an? God, The God, The One God, Allah, Shiva, and all the rest, there is only One according to the Qur'an there are no others at all, there are no fallen angels pretending to be Gods, there is none of it, and your prayers to the Ultimate God are known and can't be misdirected at all, because God is not an Idiot who needs to be called by some certain name like a phone number. You can call God whatever you want, Dog God, God is the Dog God is God not? Who is my prayer going to be misdirected to? Yet, if my understanding and concept is wrong (which yours probably is pretty messed up since you bothered a person about using the word Allah to refer to The One God) then my prayers are going towards nothing that is real. For example, if I think that some piece of Fabric is literally The God or A God and can help me, or The Moon can help me, then I've got some ridiculous opinion that I'm following which doesn't seem to match up with reality. Yet people can dispute this, and if there is a Judgment Day, then these issues will be resolved there, including my accusation towards you where I accused you of messing around with a person who made an innocent statement due to having animosity towards the term Allah being used and trying to sort of mock it in a sideways and even hypocritical way since that same combination of letters and root and everything appears throughout the Bible as well, and according to the Bible there is really no Real God but The God, Only One, so that if Dagon is a reference to The Real God, and there is only one Real God, then Dagon refers to one and the same One Real Only God.
Or do you object?
What is your concept of God and what is God's name according to you?
Allah is not the Trinity, so if you believe God is Jesus, The Father The Son The Holy Spirit who took the form of Jesus known as the Begotten Son of God, and that is who you call God or whatever name you think is the true name of God, then that is not the same as the Allah of the Qur'an, but the term Allah is used by Trinitarian Christians who speak Arabic and they refer to God using the same term and meaning something different, just like some people don't think Jesus is God but refer to Jesus and are thus referring to a different concept.