Hi There,
Sorry to hear the trouble you're in and we completely understand the pain and agony you're going through.
Here are a few questions, we would like to hear back from you regarding the below-listed questions, that way we could zero in on the real issue.
1. When you got your site redesigned, and implemented the SSL cert (https), did you get the 301 redirects done?
2. Is the Google Analytics tracking code placed in the site where it is supposed to be placed?
3. How did you come to know about the drop in the number of traffic (organic) to your site?
4. Was the content of the site updated?
5. Was there any SEO specialist involved in the process when you got the redesign work done?
6. In the previous years when you made a lot of money through the same site, what was it that you were doing then and not doing now? Can you recall any activity that you were performing with the site that you have stopped now?
There are many more questions, what we would suggest is to get on a call and discuss in details.
This definitely looks to be SEO related issue and for some reason, Google seems to be unhappy with the new site. Could be the 301 redirects, we can only find out once we have access to the backend.
But one thing for sure, you can expect honesty from us. Whatever the reason, we will tell you the truth. After that, it's your call.
Await hearing from you soon.
Thanks,
Kumar