The solutions to this situation include timely communication with banks and improving the habit of using cards.

1. Communicate with the bank in time: contact Ping An Bank's credit card customer service to find out the specific reasons for the decrease. If it is due to misunderstanding or explainable circumstances, such as providing true proof of consumption, the bank will consider restoring the quota.

2. Improve the habit of using the card: avoid overdue, standardize the use of the card, do not spend in risky merchants, and maintain a reasonable record of consumption and repayment.