Receiving an error with HDL for Candidate Addresses

Summary:

We are trying to update all Candidate Addresses in our lower PODs to keep the PII data anonymised. We need to replace the existing addresses with false addresses.

Content (please ensure you mask any confidential information):

For this I am using this HDL metadata line as an example with this fake address.

METADATA|CandidateAddress|CandidateNumber|AddressType|EffectiveStartDate|Country|AddressLine1|AddressLine2|AddressLine3|AddressLine4|Building|FloorNumber|TownOrCity|Region1|Region2|Region3|PostalCode

MERGE|CandidateAddress|10001447|HOME|2022/09/25|GB|10 Desford Road|Desford|Enderby||||Leicester||Leicestershire||LE19 4AT

I am getting error messages along the lines of:

You can only provide 1 candidate address row for candidate {CANDIDATE_NUMBER}.