Therefore, in the design mode, you will find the advanced settings of the approval workflow have the "Lock record when approval starts" option checked by default.
Normal Process:
If there is a need to modify the record during the approval process or after it has been approved, the user who has sufficient access rights should click Cancel Approval. If "Lock record when approval starts" is checked, the record will be automatically unlocked when canceling the approval process. After completing the modification of the record, it can be resubmitted for approval.
Special Scenario:
If there are other factors preventing the cancellation of the approval and triggering the unlocking, the only option would be to manually unlock the record directly through the lower right corner.