Problems updating (Parsing response failed)

Hello,
I am trying to update nextcloud. I tried using the updater and at the first step “Check for expected files” it says “Parsing response failed” and “500 Internal Server Error”.

Log from nextcloud-updater.log says

....
[info] checkForExpectedFilesAndFolders()
[error] POST request failed with UpdateException
[error] Exception: UpdateException
Message:
Code:0
Trace:
#0 /var/www/virtual/###/html/updater/index.php(1361): Updater->checkForExpectedFilesAndFolders()
#1 {main}
File:/var/www/virtual/###/html/updater/index.php
Line:412
Data:
Array
(
    [0] => 0
)

I am grateful for any ideas on what to do. I guess its good to know, that I am completely new to SSH, just taking my very first steps.
I tried looking for already existing answers but couldn´t really find something.

Thank you in advance

Hi @kollala,
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