Keycheck - interpolated mode - Escape?

Hello,

I am getting the following error message:
{“status”:“error”,“message”:“Error:</strong> The username USERXXX</strong> is not registered on this site. If you are unsure of your username, try your email address instead.”,“args”:}

Is there a way to use
Error:</strong> The username USERXXX</strong> is not registered on this site.

in the Keycheck in the interpolated mode? How to enter it as I am getting error message because of the characters? Instead of USERXXX there should be <input.USERNAME>

Thank you!

BLOCK:Parse
  input = @data.SOURCE
  jToken = "message"
  MODE:Json
  => VAR @message
ENDBLOCK

BLOCK:Parse
  input = @data.SOURCE
  leftDelim = "</strong> The username "
  rightDelim = "</strong> is not registered on this site."
  jToken = "message"
  MODE:LR
  => VAR @US
ENDBLOCK


IF STRINGKEY @GG Contains "The username "${US}"</strong> is not registered on this site. If you are unsure of your username, try your email address instead."
data.STATUS = "FAIL";

END