Exchange Account Disappears Frequently After S6 Update

Hi, I am using a stock S6 in the UK and received an OTA update (Vodafone, screenshot attached) two days ago. Now my work exchange email account in the Gmail app has disappeared (no sign of it, all the emails and settings disappear). I can set it up again and it receives email for a few hours but then it randomly disappears again. I have two other accounts (gmail and IMAP) and both are unaffected.

Seems like a software issue. I've flushed the cache but can't find the solution - anyone have any ideas?

Thanks

Bryce

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