Form list download failed (for my project)

Hi, we are having a data collection that is meant to be started soon. Although, some of our enumerators keep getting this error “form list download failed” while getting a blank form.

I tried all the possible ways including rechecking the URL, password and user name, having my xls being checked yet can not proceed. Can anyone help me on this ASAP?

@Somaya11, have you followed this support article to configure your app correctly?