You have a few options


You can change the recovery model of your databases (I,.e from full  to simple)



If you do this you will loose the ability to do point  in time recovery on that database because to you don’t have any transaction log  backups

or

Configure your maintence plans to backup & shirnk the transaction logs , this should sort your problem out

You can also use this syntax to truncate sql  logs

DBCC ShrinkFile (Database_name, 2)

BACKUP LOG Database_name WITH TRUNCATE_ONLY