Can't see my messages

I had a few hundred messages in my inbox, today I can see only 70 of them, going back to 1st January this year. Have tried both the old and new website interfaces.

I have been a Zoho Mail user for a number of years and never had this problem. I used to click to a new page by using the pagination icon at top right on the old interface. This now shows only a single page with the 70 recent messages. Zoho's support in reinstating my messages would be appreciated.