Found illegal Freemarker variables in the template: ${replayto_name}

Following: 

I have the same error message occurring for meeting registration:  "Found illegal Freemarker variables in the template: ${replayto_name}"  

This is what happens when an invitee attempts to reply to a meeting sent from Zoom. Is the variable in the built-in template mistyped? Should it be {replyto_name} rather than "replay"?

Experiencing same error message today, although registration for my meeting was tested yesterday and worked perfectly.

 I'm also getting a similar message - I have a meeting set up for registration with Manual Approval linked to JotForm - when someone registers and we try to Deny them and send an email we get "Found illegal Freemarker variables in the template $(hostEmail?html)"

I have the same issue, I'm trying to add the email variable for the outlook calendar URL. It is returning this error:
"Found illegal Freemarker variables in the template: ${addToCalendarUrl}"