not automaticaly erase in tape

[mistert59]

Hello and sorry for my poor english :) 

I'm jobs for full save weekly, this save are duplicate in tape with for keep data for 4 weeks (i have 20 tape for rotation), 

all Wednesday, i change the tape with a tape overwritable, but backups in tape aren't erase automatically and my tape is full quickly. 

I don't know why i have this problem and i wasn't changed my configuration 

i need your help please 

thank you 

[CraigV]

It possibly has to do with your retention time on the tapes. Check this, make sure they are correct, and then try the job again. The tape should be expired by the time it is required again.