Avanti Dryer starts spinning but frequently gets stuck

Hi,

This is my first post here. I'm VERY new to dryer repair, but I want to learn more.

My dryer is a ~4 year old "portable" model from Avanti, and it has been working well enough, but recently, it's developed a problem. When I start a drying load, the drum starts spinning, but it frequently stops, as if it's getting stuck.

I took a video of what's happening with the back cover off. Here it is: Whats wrong with Pinny's dryer? - YouTube

You can see the dryer getting stuck around 1:12. Also, there's a wheel inside the dryer that, as you can see, starts turning at the beginning but then stops for most of the video.

I really appreciate any advice you can give me.

Thanks!
Pinny