So basically everytime i play multiplayer the game changes my skin with other player's skin and its annoying because some love playing with our own skin.

Thank you for your report!
However, this issue is a Duplicate of MCPE-48207.

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.

Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – 📖 Game Wiki

Ik its duplicated issue but i reported it again because they reported that last year and its still going on. Also im a beta tester for the new minecraft pe version and the bug is still there. I think it has to do with the skin creator so plz fix it before releasing the 1.15.