The operation Elements cannot accept the arguments Issue with CloudDB

Hello Everyone
I was creating a food delivery app and used cloudDB to take the input of users to store it in a list view . But I got this error message. The operation Elements cannot accept the arguments["List"]. I am attaching a copy of my code. Please get back to me as soon as possible.

Unable to view your blocks properly

Export your .aia file and upload it here.

Here is a wild guess, to tide you over until you can post source code:

When appending to a CloudDB list, be sure that the value for that tag has been initialized to a list.

P.S. I would avoid using tags like "List", to avoid collisions with reserved words. Any way, list of WHAT?