Hello @Maya6 , I inform you that at the time of renewal we will in any case deduct the cost of the offer from your remaining credit, which will therefore go negative, but we will not deduct other renewals. The month of validity of your offer begins when the remaining credit becomes positive, so you don't waste even a day. I also remind you that the SIM I have. it is valid for 12 months from the last recharge. Starting from the eleventh month you will only be able to receive calls. To update the expiration date of your SIM, just top up. I remain at your disposal for any further clarification.