You will need the Full Write Pledges permission at every campus of the pledge's campaign to delete a pledge. A pledge follows its campaign's campuses, never the person's.
You can delete a pledge from any screen that lists pledges by:
Going to Contributions > Pledges in the left-hand navigation menu, opening a campaign, then selecting the Pledges tab.
Selecting Contributions > Pledges in the left-hand navigation menu and then by going to the Pledges tab.
Choosing a person's profile, going to the Financial tab > Pledges tab.
Deleting a pledge
Open any screen that lists the pledge you want to delete.
Find the pledge in the table and click the 3-dots menu (⋯) at the start of its row.
Select Delete.
When the confirmation message appears, click Yes to finish.
Good to know
Tip: Deleting a pledge does not delete any contributions credited to it.