The problem is partly with CX as about 10% of my flights just don't post. But, I've never had a problem with posting to AA so it is also something in BA's control.
The people at Sunbury who deal with missing miles are of variable quality. I had one numpty tell me that OW flights over 2000 miles still only earnt 60 points in F. Oh, and that as it was only a two class plane i should only be earning J Tier Points! However there are others that are pretty good. As ever, apply the FT rule of call again if you don't like the answer. You could also consider a letter with all the details to what'shername who runs the EC.