Android update crashes Email Outlook account on Samsung Tab

My S5 Tab had a major Android system update which optimised all apps.  Outlook account, in Email, could no longer send emails but could receive.  Worked OK from browser, Phone (S8) and PC and Oulook Ap

Clearing Cash no help. MS CHAT support no help.

The outgoing server settings were those recommended by MS support.

Deleted account from Email added new account all now working from different server.

No idea why or why MS support couldn't work it out.