Can't play friend's room with Data.

Please add more detail as to what your issue is. "can't play friend's room with data" doesn't really tell me anything.

Em..I not good English.
I can't join friend's room with data.

Go to Game settings > Profile
Do you have cellular data turned on? If yes, this is possibly related to MCPE-44884.

Yes I turn it but can't host multiplayer game.

Thank you for your report!
We're tracking this issue in MCPE-44422, so this ticket is being resolved and linked as a duplicate.

If you would like to add a vote and any extra information to the main ticket it would be appreciated.

If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.

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