How to redeploy a modified form but after receiving submissions?

Hello,

Indeed, I have a project with already 352 submissions and to this project I have added some questions
now need to deploy the new project. When I am trying here below is the error message i am getting:
There has been a problem trying to replace ${b} with the XPath to the survey element named ‘b’.

Please help me.

I guess you have not variable “b”
in excel just search " ${b} ", maybe there is a error expression.

If you solved this, just redeploy form.

Thanks