Gift applied to Pledge or Recurring Gift in Error
It is not possible to unapply the gift to the Pledge or Recurring Gift.  Once a Cash gift is applied to a Pledge or Recurring Gift, the gift type changes from Cash to Pay-Cash or Recurring Gift Pay-Cash.  There is no option to unapply the gift.  The gift can be adjusted to $0 or it can be deleted. If you Post to a General Ledger software, it is recommended that you Adjust the gift so you have a trail of what occurred.

Gift NOT applied to Pledge or Recurring Gift and should have been
If the gift is NOT POSTED, you can apply the Cash gift to the Pledge or Recurring Gift directly from the gift itself.
If the gift is marked POSTED, you cannot make any additional changes to it because it has been "posted to your general ledger."  If you make changes after the fact, the amounts in The Raiser's Edge could get out of line with your "general ledger." Even though you may not be posting to an actual general ledger program, you "freeze" the record when you post a gift. To change a posted gift, you must either adjust, delete, or unpost the gift.

For a single gift:
  1. Adjust the payment gift to zero (to keep a record) or delete the payment gift (if you do not wish to keep the original payment record)
  2. Recreate the gift  
  3. Apply the gift to the appropriate pledge, recurring gift transaction, or planned gift

For multiple gifts:

  1. Create a Gift query for desired gifts.
  2. Run the Unpost Gifts Utility based on the query created in step 1.
  3. Apply the gifts to the pledges/recurring gift in question.
  4. Use the query created in step 1 to globally mark the gifts as Posted.

If you do not interface with Blackbaud's General Ledger or another accounting package, you may run the Unpost Gifts plug-in to globally change the Post Status from Posted to Not Posted. Gifts with a post status of Not Posted are included the next time gifts are posted to the General Ledger in Administration. If you post to an accounting package, this could cause duplicate entries in the accounting package. 

Note: This plug-in does not unpost gift adjustments, which can cause reconciling issues if any gift adjustments were ever posted to an accounting software. If that's the case, follow these steps to unpost gifts with adjustments.