Inserting Horizontal Lines In Word Documents Quickly?

There must be someone in Brattleboro who knows enough about Microsoft WORD to answer my question.

Normally, when you want to quickly insert a horizontal line into a Word document there is a keyboard shortcut to save you time.

Example: To put a simple divider line between two paragraphs in a document, just type 3 dashes — and hit
‘Enter’ immediately.

Voila! You get a nice horizontal line to the page border.

You can also change the type of horizontal line you are inputting by changing the characters you use for this
short cut. Three asterisks***, three underscores___, three equal signs ===, three pound signs ###, and three tildes ~~~, all give different line styles.

 I’ve been doing this for years. A few days ago, it stopped working. I must have inadvertently turned this
feature off.

How can I turn it back on???????