Problem
Services, materials or equipment items aren't appearing in your Pricebook or when trying to add to estimates or invoices.
Solution
Confirm equipment is active in Pricebook
Go to the navigation bar and click Pricebook.
In the side panel, go to the appropriate tab, Services, Materials, or Equipment, based on what's missing.
Click Filters.
Under Status, select Inactive and click Apply to reveal hidden items.

You can activate items one-by-one, or bulk activate the items using Edit Mode.
Check the previous Pricebook version and bulk activate items
Go to Pricebook > History.
Click .XLS in the After column to download the most recent imported file.

Open the file and locate the Active column.
1 means the item active in Pricebook
0 means the item is inactive in Pricebook

In the file, update 0 to 1 for the items you want activate.
Save the file as Excel and import it back to Pricebook.