1. Work certificate and income certificate are not helpful for quota adjustment. These are all the materials needed when you apply for a card, and they are not the basis for adjusting the quota. What ICBC recognizes is "recommendation letter" or wealth management account, the contribution of star customers and so on. Or you usually spend more, and the repayment is normal, which is reflected in the transaction details. 2. It usually takes three months to apply for quota adjustment. In addition, during this period, you didn't have any overdue repayment. 3. To adjust the credit line, you need to fill in the Peony Credit Card Business Application Form (only personal information, card information and credit line adjustment) and provide details of nearly three transactions, which can be issued and filled in at the application outlets or local card issuing centers. If you meet the conditions, the other party will accept it.