Android TTS (Text-To-Speech) doesn't pronounce isolated word correctly

The TTS pronounces "az-zumaru" instead of "az-zumar" when passed the following Arabic word (title of a Sura): ٱلزُّمَر

Any suggestions what to do to produce the correct speech? Is there some unicode character that will tell the TTS engine that "no Tanween is needed here" (for example)? My guess is it is adding a tanween when it should not, but I'm not sure as I'm not an expert in this area.

I've tried different spellings (without diacritics) from https://en.wikipedia.org/wiki/Az-Zumar but it seems to pronounce it with a trailing "u" sound in all cases.

If part of a longer sentence, the word appears to be pronounced correctly.

I've also tried different android voices (e.g., ar-xa-x-arz-local, ar-xa-x-arc-local, etc.) and they all seem to add a trailing sound for single words.