How do I get my Construct3 project folder to open?

I been working on a project with a peer and we are collaborating using GitHub. We've been sharing files with no issue for the past couple of days, but yesterday after they committed their updates and I fetched them I am unable to open my project. I keep getting the error "Failed to open project. Check it is a valid Construct 3 folder project."

I've scoured the forums and have tried implementing some of the fixes that I've seen with no luck. I've opened up my browser console using F12 and it tells me that the error is "Exception Opening: cannot find object type named 'billingBtn'. I've looked through my project file and see that there is an object typed named 'billingBtn' in the objectTypes folder of my project so I'm unsure to what the issue could be. This project contains sensitive work information, so I can't share it, but I'm hopeful a pro here knows the solution!

I ended up restoring the project from backup like you suggested and I'm able to get back in. The 'billingBtn' object is present in the project.c3proj file and I checked by opening the .json in notepad to make sure it was there. Might have been a weird incident. My concern is how often something like this will happen since we have a couple of people collaborating on this project since it's quite large.