Judaism, Christianity, and Islam all claim to believe in the god of Abraham, but they have substantial differences when it comes to what the characteristics of that god are. Even within these religions, there is substantial disagreement and therefore a variety of views and denominations.
And then compared to Dharmic conceptions of the ultimate god or reality, there are typically great differences as well.
-Some people believe god is transcendental and above spacetime, responsible for all creation, while others believe he has a physical body and/or only created a subset of things.
-Some people believe god is separate from creation while others believe that all creation is a part of god.
-Some people believe in benevolent and loving deities, while others believe in wrathful and torturous ones.
-Some people believe god answers prayers and knows everything about a person's life, while others believe god is distant or uninvolved.
-Some people believe god cares what religion a person is, while others do not.
-Some people believe god will judge people after one life, while others believe people reincarnate and receive experiences based on their actions.
-Some people believe the ultimate reality is a rational conscious force, while others believe it is a more vague life force of some kind.
-etc
These are all vastly different views of the ultimate reality, so it's of no surprise that one person's idea of god is labeled as a different god than another person's. A fundamentalist Christian simply has a different god than a deist or a liberal Hindu, whether they both use the same word or not.