External hard disk not backing up Macbook Pro

I have a Trekstor Detestation maxi light 3.0 external drive that I use to backup my Macbook Pro (2019)
I’ve been using it now since 2014.
It no longer shows up in the sidebar, compared to another backup drive that does.
See screenshot of Disk Utility. The disk is clearly full. Recently the Trekstor had been trying to create free space, which went on forever to the point that I had to interrupt it. Then it got on with the usual backup.
Problem now: no longer appears in sidebar and doesn’t backup.
Is there anything that can be done?
Erase content from Disk Utility, for example?
Many thanks.
Joseph Quinn

Time for another disk drive!

I have so many questions but too little information was provided in your post.

This is like 103 in disk drive years :slightly_smiling_face:
Probably time for a new drive.
Maybe try erasing, but I wouldn’t trust it anymore.

1 Like

That seems to be the consensus.
Many thanks.

Situation clear.
Many thanks.