I have the lg x charge and the wifi-manager has been off and it doesn't make any difference at all. started 2 updates ago and after the last auto update the wifi drops every few minutes.. Mark
As mentioned before, the best solution is to uninstall the Cricket Wifi Manager applications off your phone or disable them if you can't uninstall them. This application is horrible and will cause issues like you are describing.
Try turning it off in the mycricket app. Tap the best in the top right corner then scroll down and tap device settings. The wifi manager is a toggle switch. Good luck. Turning it off has kept my wifi on for almost an hour now. Two hours ago I had to reconnect three times just to get into my bank app.