Currently, vet/rescue/breeders cannot edit microchips. Once an application is approved, the microchips are proactively registered with the vet/rescue/breeder's contact information. The chips are automatically added to the Fi Partner's account and can be found under Stock but are unable to be edited.
If a microchip is under Active, a pet owner can edit the chip's information. See: I Am a Pet Owner, How Do I Manage and Edit My Fi Nano Microchip Account? and What Does Stock, Active and Review Mean In My Fi Nano Partner Account?
If the owner reaches out and is having issues editing their account we suggest sending them: Why Can I Not Tap Continue on My Fi Nano Microchip Registration?