Air Filter housing; different clips?

[Makhlari]

Hi all,  Whilst changing air filter for my newly aquired 2008 A6 Allroad and I noticed one spring missing from the housing. I promptly bought one off E-bay (£6.99!) and seemingly there is only one type (VAG 078129797), it has the claw on one end. However, upon fitting it noticed that the clip housing retention is different to the other one with the clip and wont go in. Pics attached. Are they a different clip or am I missing something basic ?

Thanks in advance