Unknown part in Caffeo Solo brewing unit

Spare part upon assembly of brewing unit

Fillifax

September 28, 2020 12:57 pm

Unregistered

Hello, I recently had to disassemble my brewing unit for Melitta Caffeo Solo & Perfect Milk, but had the pictured part left over upon re-assembly. Can anyone tell me what it is and where it needs to go?

https://photos.app.goo.gl/d5zs2ck2ugAqUneW7
https://photos.app.goo.gl/ibSsQZjUf1JGQoZK6