Outlook 365 spell check prevents manual editing of errors

Same here - but mine has an added issue that if it try to edit the word, even just one letter, then it often deletes a message in my inbox! The cursor is in my right hand window with the email open, and remains there, but a message in the left hand window is deleted. And does so each time I try to delete a letter in the word - so I then have to go to deleted messages and reinstate them. And of course, still the misspelled word remains incorrect, so I need to delete the whole word, starting with a space to the left [i.e., not with the cursor up against the last letter of the target word, which would delete emails...], delete the whole word, and retype it correctly, lest the whole process begins again. It is slowing me down enormously, and is a vast retrograde step compared to pretty much any other spell checker, ever... [the one on this webpage is vastly better than outlook now - which used to be pretty good, better then Gmail, but now Gmail is massively better than latest new iteration. anything is better, tbh]. It is especially bad if you write emails in a technical area, where the suggested words are just irrelevant. 

I guess I will have to find a way to turn off spell checker or write in Word/Google docs, and then paste across...