"Front template has a problem"

I was able to make a bunch of cards, but then found the following message when I went to study them:
Front template has a problem:
Found ‘⁨{{type:}}⁩’, but there is no field called ‘⁨⁩’

I have tried looking online and in the help guide linked but am still stuck.

Try replacing <BackFieldName> with Back.

That placeholder (or whatever it should be) is intepreted as an unclosed HTML opening tag (which is invisible), hence ..there's no field called ''.


Thank you SO much! That solved the issue.