unfinished migration

unfinished migration

Dear Zoho staff, first a big thank you for providing the free tear service, it means a lot for me to be able to outsource to you the mail service.
I've made the migration of my old email via IMAP and it states is completed however the number differs:
Folder Name Total Msgs Migrated Msgs
INBOX.Old Mail 1568 1191
INBOX.Sent 1094 1094
INBOX 4065 3951
INBOX.Drafts 46 46
INBOX.Trash 13 13

I wonder if this is because I've already finished my free 5Gb or if there are other reason behind.
mail storage tab shows 0 Gb used so is not reporting the space really utilized.
No error so far have been reported.