Upload with limited filesize (10MB) with iOS desktop app

Files > 10MB (hard limit) are not uploaded via nextcloud iOS desktop App

message in the log-file is:
> > > > ||folder/file.indd|INST_NEW|Up|1564981504||27314281||9|Server hat “510 Not Extended” auf “PUT https://cloudadress.com/remote.php/dav/uploads/admin/1584584359/00000000” geantwortet|510|0|0||||

translation: Server answered “510 Not Extended” on "PUT "

Additional Infos:

  • I’m running two accounts via the app - one is working, one is not.
  • The one that is working is synchronising with a public cloud (no admin access), the other one is a private cloud on a hosted server -> no server admin, but nextcloud-admin
  • Uploads via browser are working without any problem, even for big files.
  • Downloads via desktop app work without any problem, even for big files.

Nextcloud version: 17.0.0.9. (working one is 16.0.3.0)
Nextcloud desktop app for iOS: Version 2.5.1final - build 20181204
Operating system and version: unknown
Apache or nginx version: unknown
PHP version: 7.3

Is this the first time you’ve seen this error?: Yes

Any idea?
Thanks for your help!