Greekglish State and City from Firefox

hi, i just see this big problem for me,
When I create a listing from chrome and put city for example “Αθηνα” the fileds are ok: Country: GR – State: Κεντρικος Τομεας Αθηνων – City: Αθηνα

BUT
when the same user create listing from Firefox with the same word “Αθηνα” the fields are not Greek and they are Greekglish!!! 🙁 and the results are:
Country:GR – State: Kentrikos Tomeas Athinon – City: Athina

And the system CREATE 2 different city name for that! 🙁

From Chrome: https://prntscr.com/48igvf
From Firefox: https://prntscr.com/48ihpa

what can I do? any help please?