Why are some emails clickable and some aren't?

I need them all clickable.

I have a column of email addresses - some are hyperlink clickable and some are not.

On the ones that aren’t, if I do insert>hyperling, they switch to “Mailto:xxx@yyyyyy” but I want consistent formatting.

It’s so random I can’t tell you what’s doing it. At one time I caught it not honoring email addresses that were pasted in with a space at the end, but many addresses don’t work even after trimming the beginnings and ends?

Thanks for looking