Failure to download "Blank form" on ODK collect from wepi

1. What is the problem? Be very detailed.

I installed the ODK collect app onto my android phone, then I lauched the app and set the parameters for wepi : url, username, and password.
Then, when I want to download the blank form from wepi it doesn't work 'message : (Version:: 1,0 ID:....) - Failure. See below

2. What app or server are you using and on what device and operating system? Include version numbers.
I'm only using wepi and ODK collect v1.30.1. I'm using my phone android

Thank you very much for your help

Welcome to the ODK forum, @Hugo! We're glad you're here. When you get a chance, please introduce yourself on this forum thread. I'd also encourage you to add a picture as your avatar because it helps build community!

Wepi (https://www.wepi.org/) is not part of the core ODK ecosystem and therefore not supported on this forum. It looks like you can report errors with their system to them via their service desk.