I am suddenly unable to save assets or create new libraries within my account. I was able to initially, but not it’s not working now. I tried to save a header as well as other elements and when I go to check the Assets, nothing new is there. Any ideas on how I can fix this?
Try clearing up the browser cookies. Also, you can not save the global sections(like header) Along with following elements - * Wix Apps (e.g., Wix Stores)
- Forms
- Hamburger menu
- Input fields
- Lightbox
- Pro Gallery
- Third-party apps (e.g., Instagram Feed)
I didn’t realize that about the header, as the right-click gave me the option to save as an asset. Nevertheless, I cleared cookies, etc and tried saving a few different sections and still nothing is saving into my libraries and I am not able to create a new library (even when it gives me the option when I am trying to save the asset).
Contact the support…Not the AI, but the real people 
Apparently its a known issue - Wix Studio: Unable to Save as Asset | Help Center | Wix.com . For now, you can copy the assets you want to save and paste it somewhere in the website. If you have many, create a seperate template for saved assets. You can cross copy paste elements from one website editor to another.
I will do that. Thank you very much for your help!