External hard drive issue – errors on one MacBook Pro / no errors on other MacBook Pro

I'm having trouble with an external hard drive. When I use it with my old MacBook Pro (15" Intel, 2016) there are no issues with it, but when I use it with my new MacBook Pro (16" M1, 2021), I get errors –. it disconnects, I get errors writing to it/reading from it, etc. (Both computers are running macOS 12.0.1; Apple Hardware Test and Diagnostics show no errors on the new MBP.)

When I run Disk Utility's First Aid on the old computer, I get no errors, but on the new computer I usually get this:

Checking file system and repairing if necessary and if possible.

Volume is already unmounted.

Performing fsck_apfs -y -x /dev/rdisk6s1

error: failed to read container superblock

File system check exit code is 8.

Restoring the original state found as unmounted.

File system verify or repair failed. : (-69845)

Operation failed…

I've tried Disk Drill too. On the old MBP it shows no issues, while on the new MBP it says "439 unreadable sectors":

I've tried reformatting the drive, but it makes no difference.

Any suggestions what could wrong?