I have a recent problem on Word 2016 for Mac. I have spelling and grammar check running as I write. The spellcheck will pick up on a misspelled word, I will right click on it and select the correct spelling. Sometimes, the spelling will change but the red line remains. It will only disappear if i put the cursor at the end of the word and press space bar. This of course adds an extra space (if I've returned after completing the sentence) which immediately brings up the double grammar line, so i have to delete it again. I realise this is a short process, and it happens intermittently, but it's not working as it should and it's slowing down the process.

I do not have a Mac. To help someone else help you, could you tell us which release or version of Word you are using?

(The various updates for Office 2016 have different features/problems.)