App Installation Failed: mkdir() no such file or directory

I've installed Akaunting onto a VPS and have it running in a docker container through a Nginx reverse proxy.

Akaunting itself seems to be running as it should, however whenever I try to install any App into it I get the error message in the title. The worst part is that there is no evidence elsewhere of any sort of error. No log messages, no hints, nothing. I've double checked file permissions both inside the docker container and the volumes I've mounted outside.

Any clue as to what this might be?

It seems you have a problem with file/folder permission. Feel free to check your logs.

@Denis I did mention that I already looked everywhere I could and there were no log messages that indicate what the problem is. Do you have a specific log file in mind that I've missed?

I also mentioned that I double checked the file/folder permissions before making this post. For testing purposes I even tried granting excessive privileges (777) and even that did not work.

Regardless, I have moved away from using a docker container for this; I'm not happy about it but at least I can install apps now.