Problem In Extension Developing

I Have Created a activity and i want to this that activity. But How can i do this?
any one has solution?

What does this line mean ?

be more clear:

don’t know about other errors but your public class is “PaytmWebviewer” and you extension name is “Paytm” they must be same.
moreover, send the error log you received from Kodular to you email, it will help us to know the issue