Annoying error messages when working on AE

Hello, I hope someone can help me solve this problem. 

Whenever I want to open a past project with images/videos/vectors sourced on an external hard drive an error window pops up with an message that says "After effects error: File exists but couldn't be open for reading: "/volumes/seagate/expansion drive/design/...". (3 :: 0).

In addition to this, when I create a new project, I can work with elements sourced on the external hard drive, however, if i want to save the project it gives me an error message saying the file cannot be saved because After Effects has no permission to write on the HDD. Which is completely illogical because the hard drive isn't secured nor have this problem when working on another Adobe program. Also exporting a video directly from AE or through Media Encoder gives me an "Error code: -1609629695" that only happens if the video has elements sourced on the external HDD, thus when i relink the elements to a source internal to the PC it lets me export the project with no problem.

I work on a iMac 21.5  macOS 12.4 8GB RAM.

The external drive works fine, i haven't had any issue with the graphics, etc. This is the first time i have this kind of problem and i don't know how to solve it. I hope anyone here can give me an answer because the whole back and forth I have to do with the files is starting to get annoying and time consuming. 

Thank you.