Credit Locking - it will lock Points (or proper money equivalent) above the number you set, for the number of days you set. After the lock time is passed, the locked funds will be released. Setup Credit Locking let you avoid fraud from CPA/GPT or Offer Wall offers. The amount compared is the amount which would be credited to member account (not the one sent in postback, but parsed one). Credit Locking feature works only on postbacks. It doesn't work with manual approval.
To enable/disable Credit Locking, go to Admin Panel → Security → Credit Locking
You can select for how many days and for above how many points you want to lock Points.