Hi @Ana_Antolin,
Welcome to the Forum!
When you get a chance, please please introduce yourself here.
It looks like you forgot to include the two-character language codes. For Banglali/Bangla the code is (bn). You can read more at the two links below:
http://www.iana.org/assignments/language-subtag-registry/language-subtag-registry
I've edited your excel file (see Bangla_Test.xlsx (18.5 KB) ) to include the code in the headers.
I've converted it online at and tested it on Enketo and it seems to be working well.
I hope this helps!
Best,
Andrea