I have missing clients and other data,was working well until today what can I do to get it all back please help

Hello Mummydea-Hotmail, 

Welcome to the Community page, 

Could you try some troubleshooting steps to see if that resolved your issue, 

Can you clear your cache and cookies?https://  https://quickbooks.intuit.com/learn-support/en-uk/manage-login/clear-cache-and-cookies-to-fix-issues-when-using-quickbooks/01/368183

could you try in an incogetio/private window

Let us know how you get on.