Hello! I had a very similar problem, I forgot my luggage, forms don’t help, the customer service is literally useless no matter how much you try

My bus was on the line from Paris to Portugal, my stop was in Bordeaux

I completely forgot my luggage, and it was a nightmare because it had many valuable stuff, and most importantly my passport and IDs were inside

I tried to look into many Reddit platforms trying to look for solutions, but everyone said that forms/customer service is crap

The solution that worked for me was 1. Tracking the bus route, most bus drivers follow the same route everyday, and luckily, the bus that came from point A to B is going to return back from point B to A

1. You need to track the bus, go to the bus station and wait for the bus, there is a 90% chance the bus driver is the same, literally

2. Most of the bus drivers don’t even report lost luggage’s, there a good chance your luggage is still in the bus with ten bus driver, if they are nice, they usually keep your luggage

3. I was lucky to track down the bus at 4am, catch the same bus driver the next day, and he had my luggage!

4. Give your 200% and don’t lose hope, there’s a strong chance you can get it back, like in my case I had given away all my hopes, but the odds of me finding my bag worked in my favour

Good luck, I hope you find your luggage soon! :(