Pro Sites page changed without me making the changes.

I have been working on my pro sites check out setup for a couple weeks. I have a couple support tickets for customizations and fixes. When I logged on this morning it was like a new pro sites had replaced mine. The pro sites page changed from https://myactingwebsite.com/my-acting-website-pro-2/ to https://myactingwebsite.com/pro-site/. My extensive custom code for the pricing tables and the contents of the table disappeared and reset to default almost entirely. Can you tell me what happened, how to get it back and if this type of thing happens often?