1. Go to Giving > Contributions > Search 
2. Enter contribution details into search fields
3. Click Search 
4. Select checkbox beside donations which need to be moved
5. Click drop down list at bottom & select Move Contribution / Receipts
    Note: You need to have the Move Contribution / Receipts right to perform this action.   
6. Click Find Contributor & locate new contributor
7. Click OK in pop up window to finish