Unable to delete or Upload files in Report Server

Hi,miwundu .I am glad to help you.
Based on your error screenshot, I think it's likely that you're having problems with the report server database itself.

Regarding these  databases, could you please query their Views, especially Execution.log/log2/log3?

These views record detailed information about report execution, including execution time, status, and error messages. You can query these views to find error logs for a specific time period.
Try to reproduce a screenshot of your error report and quickly locate the specific message based on the execution time.

Combine this with the report server log files to find additional error causes.
The general report server files are usually stored in the following folder C:\Program Files\Microsoft Power BI Report Server\PBIRS\LogFiles
Please focus on PeportingServicesService.log, which records events, errors, and informational messages related to Reporting Services services, including information about user changes to the report server configuration, such as changes to connection strings or security settings.

If you can quickly localize the problem through log messages, this can help to help you better resolve the error.
Sometimes cached information can be intrusive, and you can try clearing your browser cache to reduce the number of intrusive items for troubleshooting during the checking process.
I hope you find the link below helpful, he logs the same error messages:
URL:
Solved: Error Uploading Reports on Report Server - Microsoft Fabric Community
 
I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Carson Jian,
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