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1. Contact the microchip registry and request that the registration be removed.
2. Once the registry confirms that the registration has been removed, go to Animals > Microchip Registrations in RescueGroups.org.  Select the checkboxes next to the chip registrations you wish to remove.  Use the dropdown Actions menu to choose Delete.
3. Re-register the microchip to the new owner.

Common microchip registration errors and messages

This microchip code has already been registered in the registry. You must contact the registry and have them remove the existing registration before you can re-register this microchip.

The microchip is already registered with the Registry.  If you are trying to re-register a microchip you may need to contact the Registry and have the current registration removed before you can retry the registration.

The pet is missing a required field. Please edit the pet and select a value for the field.

The registry requires a value for one of the pet fields, and that value isn't currently provided on the animal that you are trying to register.  Edit the animal and update the field that is shown in the error and retry the registration.

Registration of PetLink microchip not saved for non-PetLink registry.

As mentioned above, Datamars microchips are sent only to the PetLink registry.  This message means that the registration of a Datamars microchip will not be sent to a non-PetLink registry (eg., FreePetChipRegistry).