Lewis not sticking to their promises

Had a problem with lewis last month for taking debit orders on dates they shouldn't have they promised me they fixed the problem of the date it goes off, and again this month the debit order goes off again earlier than agreed on its suppose to go off the 1st off each month and yet it goes off in the 28th its starting to worry me that I can't trust them having access to my bank account, this is becoming a big problem for me