I see a thread on this from June 2020, but it happened to us a couple of weeks ago. One of our secondary email accounts locked and reported mailbox as full. The slider says less than 1Gb spare from 25Gb after a clearout, but:
Please help with
1 How to reliably remove things, as after deleting and then emptying trash, usually nothing happens
2 Does the 25Gb apply to all the emails, or one limit each?
3 What happened to the upgrade to 60Gb?
1 The error message points us to webmail, but there is no help there at all
2 It would be helpful if it could show us where the worst of it is. There is sorting by size, but you have to do that for every folder one at a time