I messed up addressing an envelope - can I stick my stamp on the new one with sellotape?

[MrsFogi]

or is there some rule against this. It's a new stamp but of course is no longer sticky as I've peeled it off the original envelope.

Yep on with selotape or pritstick

I thought you are not supposed to sellotape stamps (like you I think there is some rule. I would glue it on. Or if you have one of those double sided sticky photo mounts, that would do.