How to remove residue from plastic?

[Ria P]

I did buy the sticky stuff remover to use on other things and will try the butter/peanut butter removal method next time on hamster things. Thank you all for the tips.

Impatient me had already had a heavy handed go before i checked replies, stupid i know, and made a right mess of it by dulling the plastic. Lesson learned.

Ended up with a perfectly functionable but tatty looking Duna Multy so cut the offending area out, made it into a window and covered marks with butterflies.