Find Sessions return empty,Join Sessions Error

Hi,l have a question to ask.l’am using unreal engine 4.18.3.In this buleprint I have 3 buttons,One is Create,One is
Find and one is Join.When I press the button in server,It says Created. And then I clicked the Find Button it says
Find Ok. But when Iclicked the Join Button ,It says Join Error. I think the result of the find sessions is empty .Why
would it Be empty?And Why I can’t join the sessions but some of my friends can do it in their PC?Please help me,I’am
hurry .Thanks

You might be getting a travel error. I don’t know if its required but in my setup of basically the same the map argument is ?listen, you’re missing the question mark, I really don’t know if that is required but I have almost the same setup in my project and that’s the only real difference. The only other thing I do is since your using only element 0 from the array, why not skip the join button and feed the findSession->OnSuccess directly into the join Session using get (0). Just for the sake of testing, if you did that your setup would exactly match my setup which seems to work

dear there,Thank for your answer.I did some changes,But the problem still happened.

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