Related movement errorsExternal validation
CDS20001Related movement not (yet) found
HMRC explanation
What to check across the Related movement errors
A movement the declaration refers to was not found, has not arrived yet, or does not match. Check the reference to the earlier movement and its details, and whether that movement has been recorded.
A declaration that clears CDS can still be wrong
The free eligibility checker confirms your import activity and whether a free post-clearance audit applies. No data upload, no commitment.
Source: HMRC, Customs Declaration Service error codes, Open Government Licence v3.0. GOV.UK publication · Licence