@kirstenli this is a known bug with Adobe Illustrator 29.7.1. The easiest fix is to go to your Swatches panel. In the bottom-right corner of the panel, you'll see a couple of small icons. The first one that looks like a rubik's cube, you can choose to show what swatches. You may have accidentally enabled a filter to only show patterns, gradients, or other types of swatches.

Or, in the swatches panel, on the bottom-left corner is a a stack of a library books (kinda looking). Click on it and selected the swatches library. A new panel will open with the default swatches. You can then select all of them and drag them into your main Swatches panel if you want them there.

A more drastic step, but it can resolve many unexpected behaviors and corrupted settings. On PC: Press and hold Alt Control Shift as you launch Illustrator. On MAC: Press and hold Option Command Shift as you launch Illustrator. You will be asked if you want to reset your preferences. Confirm, and Illustrator will launch with its factory settings. This will reset all your custom settings, including workspace layouts and other preferences, but it can often fix bugs that are caused by corrupted preference files.