I am reading the Shi'a version of the Adhan on wikipedia (I don't speak arabic).
Allāhu akbar, Allāhu akbar
Allah is greatest, God is greatest.
In the transliteration, the term "Allāhu" is repeated twice and it is one translated by "Allah" and once by "God" which is surprising. Reading from the Adhan again, it rather appears that the term "God" in the general sense is rather translated into "ilāha" I am also surprised not to see the same signs repeated twice.
Is there any good reason to use once "Allah" and once "God" in the translation?