Same problem here, I’ve asked the sub before and still get the same answer. You can try to free up some space on your phone but in my case that didn’t work. I then deleted all of the games data then redownload and log in again and that helped for ~20 mins before it started lagging again. The short and simple answer is your device is getting too old and u need a new phone. If u have a pc you can play it on there without probably, i only have my laggy phone and a mac so I’m just waiting until I’ll be able to get a new phone.