Most credit agreements contain a clause under which the lender may prevent you from using an overdraft facility. In other words, the lender may block your access to a credit card. The cancellation of the credit facility must be based on good lending practices.
The lender must notify you of the blocking of the credit facility and the reasons for it in advance on a permanently storable copy (in writing or electronically). However, no advance notification is required if it is necessary to block the credit facility immediately, for example in order to prevent misuse or damage. However, you must be provided with the notification without delay.
Blocking an overdraft facility does not mean that you would be relieved of the obligation to repay loans already taken out. Neither does it mean that a loan already taken out would become due and would have to be repaid in one instalment.