Two slightly different Phonak receivers?

I’ve just had to replace a receiver in my Phonak P90 because the outer wire cover had broken. I bought a genuine one on eBay and it is genuine, the package has the Sonova AG label and dated November 2025. However, the wax shields I usually use don’t fit, the end diameter is very slightly smaller. The last receiver was fitted about 3 years ago by an audiologist. You can see in the picture, the one on the left is the new one and has a completely different type of wax shield, the one on the right, the wax shield fits inside. Any clues? It looks like I’m going to have to get two sizes of wax shield for the two sides.