I sold multiple items on ebay to 1 buyer and packed them into the same parcel under 1 special delivery tracking number, however I am now trying to file a lost item claim on the Royal Mail claims center and it is asking for the "Online marketplace item number"

But on ebay it is 4 unique items with 4 unique item numbers and the field only has enough character space for 1 item number.
Do I really have to raise 4 different claims under the 1 tracking ID..? That seems very not user friendly and more work on their end also.
I also have 8 other items under the same collection (different tracking/postage IDs) that appear to be lost, so I fear RM may think I'm taking the p*ss if I raise that many claims at once.