I'm trying to format the following phrases with the Heading 1 style.

English Grammar Lessons: when I try to it add it is comes up as plain text.



I've also tried:

Eng Grammar: again the same issue.

When I add other formatted text to Autocorrect, it seems to be working.

Could Word have an issue with these words in particular?

Thanks in advance.

Are you including the final paragraph mark which includes the paragraph formatting?

Charles, you're a genius.
That worked.
If possible, once I enter the autocorrect text, I would like to remain on the same line. Can that be done with another special character?
Thanks again.

Remain on the same line, but in a different style?
Use a Style Separator.