Please explain in every detail possible what you are doing, including buttons you’re pressing, in which order. Explain how you are launching the project. What keys you are pressing, in which order, on which client. Meaning, what key are you pressing to create the session? How about what key you are pressing to join the session? How many times are you pressing each of these keys? Explain what you are seeing on the screen and give as much detail about what it’s doing. As in, does the level reload? Do you see any log messages? If so, what do they say?
Take screenshots and post them to show anything that you cannot fully explain.
You will need to explain your issue with as much detail as you possibly can because I cannot reproduce your issue. Everything on my end seems to be working 100% as it should be.