Call to undefined method

I'm brand new to Opencart, just took over a client's website and moved to new hosting. When I try to go through checkout I get

Fatal error: Uncaught Error: Call to undefined method Cart\Cart::getShippingProducts()

Site is monstergardens.com. Can anyone point me in the right direction to figure this out?

That's not a normal OpenCart function, so you have a mod installed that's using it. Double-check all your ocMod files in Extensions > Modifications, and try disabling ones related to shipping to see if that helps. If you have vQmod installed, also check your vQmod files in /vqmod/xml/. The filepath of the error should tell you if it's ocMod (since it will contain /system/storage/ or something similar) or vQmod (since it will contain "vq2-" in the file path).

It ended up being pretty simple. I emptied the vqmod cache and then hit refresh in Extensions > Modifications. I think it was really the refresh that did it.

Glad you were able to figure it out.