Can't add webdav server

Hello,

I’m trying to add my webdav server but i’m having trouble to do so.
I receive this error:

Failed to check the storage at webdav://emailadress+providername@gmail.com@https://xxxx.connect.kdrive.infomaniak.com/Duplicacy: No username is provided to access the WebDAV storage.

I’ve found in the forum this problem is most likely related to the ‘+’ sign in my emailadress and should be solved in april 2020 but i t looks like it’s still a problem.
I also tried to replace the plus sign by ‘2%B’ but that didn’t help.
I will not change my emailadress so what else can I do to?

Are you using the paid version of kdrive?