There are a few steps you can take depending on your scenario

I've deleted my playlist and I know what videos it contained:

1. The videos should still be present in your content 

2. Recreate your playlist with the original videos 

I've deleted my playlist and I don't know what videos it contained:

1. Check your video content, this may remind you of the correct content 

2. Can you recreate acceptable content or locate the video files on your computer?

3. If no, contact SignStix we can either quote you for specialist data recovery or give further advice