Protection of the Talisman
Source: Tasha’s Cauldron of Everything p. 71
Prerequisite: 7th-level Warlock, Pact of the Talisman
When the wearer of your talisman fails a saving throw, they can add a d4 to the roll, potentially turning the save into a success. This benefit can be used a number of times equal to your proficiency bonus, and all expended uses are restored when you finish a long rest.