HDD randomly unmounting

Hi!

First of all sorry if this is the wrong place to ask, if it is, please point me to a better suited channel!

Anyway I've got this old 2TB HDD attached to a rpi 4b, it worked flawlessly until now, the last few days it started disconnecting randomly..

If i reboot it mounts back again.

This is the df output:

/dev/sdb1       1.8T  535G  1.2T  31% /mnt/2tb

And this is sudo dmesg | grep sdb (the device is sdb ofc).

[   14.970908] sd 1:0:0:0: [sdb] 3907029168 512-byte logical blocks: (2.00 TB/1.82 TiB)
[   14.978857] sd 1:0:0:0: [sdb] 4096-byte physical blocks
[   14.984484] sd 1:0:0:0: [sdb] Write Protect is off
[   14.989382] sd 1:0:0:0: [sdb] Mode Sense: 43 00 00 00
[   14.989684] sd 1:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[   15.044802] sd 1:0:0:0: [sdb] Preferred minimum I/O size 4096 bytes
[   15.051196] sd 1:0:0:0: [sdb] Optimal transfer size 33553920 bytes not a multiple of preferred minimum block size (4096 bytes)
[   15.065585]  sdb: sdb1
[   15.068403] sd 1:0:0:0: [sdb] Attached SCSI disk
[   22.631983] EXT4-fs (sdb1): recovery complete
[   22.660922] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Quota mode: none.

The device has an external power supply of its own, so it's not a power issue.. This setup worked for a couple of years.

I cannot see anything wrong here, pheraps is the HDD which is going bad?