EasyJet is extremely taxing with hand luggage sizes. You should always check the dimensions of your trolley carefully on their website.

It happened to me that the same trolley, which was accepted quietly and let through in the cabin at Malpensa, was put in the hold at Prague, for 1 cm difference, with a 50 € supplement.

So, from what I understand, they let you leave unchallenged, only to charge you on the return.

Staff a bit like that, so you have to be patient.

Personally, I no longer fly with this company.