360 will receive a letter if the IOU is overdue for 12 days

No, if 360 is overdue for 20 days, it is still in the internal collection stage. The post-loan department of the platform is responsible for contacting you to communicate about repayment through text messages, phone calls, etc. The collection at this stage will be It's relatively frequent, so you have to be mentally prepared. It's best if you can properly communicate with the platform. If you can't communicate, go to work and save money to solve the problem. Generally, a lawyer's letter will be issued to collect the debt after the creditor's rights are transferred!