error ''octoprint is currently not running''

my octoprint shows ''octoprint is currently not running''
it has been running for 3 months without problems

What did you already try to solve it?

I followed the instructions octoprint gave with this result

"pi@Hypercube:~ $ /home/pi/.octoprint/logs/octoprint.log
-bash: /home/pi/.octoprint/logs/octoprint.log: Permission denied''

Have you tried running in safe mode?

I wasn't able to activate savemode

Systeminfo Bundle

You can download this in OctoPrint's System Information dialog ... no bundle, no support!)

i am not able to enter the system

Additional information about your setup

OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible

octoprint version unknown, octopi version 0.18.0, printer hypercube evolution, firmware klipper, raspberry pi 4b