Hi @DreamDancer I am sorry this happened to you. As you may already know, the boosters are saved on the device's memory. If you reinstall the game or change the device you will lose me all, unfortunately. As for your friends, if your game is connected to a King account you should see random players who are connected with King account too. If your game is connected to a Facebook account you should see Facebook friends who are playing this game too. So if you are not logged in, just log in with any of these accounts and you should see your friends.
I hope this will help you. Let me know if you need more help. Have a wonderful day 🤗