Gridserve seem to have developed an odd system where they reserve £20 then when you’ve finished instantly refund the difference… but it appears as a different transaction in the timeline.
This looks wierd, and you have to do maths to work out what you’ve spent! The other issue of the first transaction still pending doesn’t really make much difference with Monzo (although with other banks you may look like you’re up on the deal).
It presumably needs some kind of special case so these can be linked.
The transactions come from GRIDSERVE UK GMM LTD IVER GBR