When I play server / realms I turn off my phone, I automatically exit the server / realms

When I play on servers and realms, I leave the Minecraft game, and when I enter the Minecraft game again, I automatically leave the server / realms, I play in the Minecraft pocket edition, in the previous version I have never automatically logged out of the server / realms , and also when playing in the "world", I play with my friends, I turn off the phone, and then turn it on, and automatically the world goes offline, and also automatically my friend leaves that world (disconnected). In Minecraft Bedrock Edition, MCPE, before if I turned off the cellphone and turned it on I didn't automatically exit, I could still continue playing on that server / realms without automatically exiting. I hope you fix the glitch.