Connect Nextcloud OnlyOffice

Hello everyone here

I have the same problem as described and solved here in the forums.
I tried to do it the same way, but how could it be otherwise, it doesn’t work for me

my environment
Proxmox as a virtualization server
Nextcloud 24 is installed on a virtual Ubuntu 22.04 server machine
Then OnlyOffice is installed on a virtual Ubuntu 22.04 server machine
Then there is an Nginx reverse proxy manager that points to both servers from No IP

That works, even if I enter meinnextcloud.de I get to my nextcloud and if I enter meinonlyoffice.de I also get to my onlyoffice

but when I enter meinonlyoffice.de in the OnlyOffice app in the Nextcloud, the first thing that came up was “Exception: An error has occurred in the document service: Invalid token”

then I searched the token and found it in the local.json

then the error came
Exception: An error has occurred in the document service: Error while downloading the document file to be converted.

Then I tried what I found here in the forum

I have in the default.json on the OnlyOffice Server
Changed “rejectUnauthorized”: false
that didn’t help at first

then I have in the local.json on the OnlyOffice Server
“header”: “AuthorizationJwt”, modified
that didn’t do anything either

then I have on the NextCloud in the config/config.php
‘only office’ =>
array (
‘jwt_secret’ => ‘zJvDeRYPzcBJpYc8m8F7’,
‘jwt_header’ => ‘Authorization’,
‘verify_peer_off’ => true,
),
inserted
then NextCloud doesn’t work anymore

I can’t go any further now

I hope you can help me