10.9.2 TM problem

10.9.2
internal TM drive (encrypted)

Drive is 2TB in size.
Latest backup: March 22, 2015


Time Machine couldn't complete the backup to "your backup drive"
The backup disk ran out of space unexpectedly. Time Machine will try to make more space available by removing expired backups during the next scheduled backup.

--------
I have manually even deleted several gigs of data from TM and this error is popping up last few days.

How do I fix it?

Any way to fix?

Updated to 10.9.5
Deleted bunch of backups, so far it's running. Wonder if I'll get the same errors once I run out of space.