Ah, I read “connecting” as connected…no prob… it’s a Battery model and not mains attached at all. Have you tried setting it up right next to your main router/WiFi point. This will prove the end-to-end solution is ok as this is the optimum possible.
Then moving away from the router it becomes WiFi neighbour issue. These issue can be based on your own WiFi signal strength and quality, but maybe simply on interferance from neighbours. It’s worth checking your WiFi channel is not congested. There are lots of free apps on Android (none on iOS) that will allow you to see what channels are being used around you. It may mean you should change the channel you are using.