Does anyone have any advice on how to claim some missing Avios and tier points linked to a BA ticket flown on IB metal? Flew at Christmas and not one of the five of us have had our accounts credited.

I tried to do a BA claim online, inputting the BA ticket number. That didn't work.

I then tried to do a claim for a partner airline. Used IB flight numbers and BA ticket number (the only one I have) but was almost immediately rejected without explaining why.

Anyone had this? How do I get the Avios and tier points credited. The outbound leg (BA metal) credited fine.