Am in a similar situation.

Flew DEL-MUC-CDG and CDG-MUC-DEL on Lufthansa 220 stock.

Am aiming to get status on Turkish and accordingly Miles and Smiles number was entered in the PNR. The boarding cards also mention TKP and yet the mileage was credited to my United account. ( Had earlier put in the United mileage plus number since was upgrading to business using Plus Points.)

Since then United has removed the mileage credit from account.

First Turkish denied the credit replying that the mileage has already been credited by another star alliance partner. Since then have sent them a request for credit and attached the boarding cards ( which show TKP) and a copy of my United mileage plus statement for the travel period which shows no credit.

However Turkish has again denied the credit saying that mileage has been credited to another start alliance partner.

Called Miles and Smiles customer care and they are repeating that mileage has been credited to another start alliance partner.

Am new to the Turkish program and please advise how to proceed now as need this credit for achieving Gold status.