I can´t upload files or create new folder

When I want to upload files or create a new folder it says its not possible or that there is an unnokn problem. I have this issue since December.
Thank you for your help

Hello there ,

welcome to the community of Nextcloud.

You started a topic in support category.
Unfortunately you ignored the template and a lot of information to help you is missing.

Please add all necessary information like Nextcloud version, webserver type and version, os version, related log file content.

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