Hi there and welcome
Can you remove the power to the printer and let it sit for 10 minutes (so unplug it from the power supply)
Then connect it, turn it on and then let it go to sleep and tell me if it then starts please.
Can you tell me please the make and model of your wifi router?
In your web browser go to http://192.168.0.1 which is the interface for the router
the default username is ***** ***** the password ***** *****
Once signed in, locate the routers bandwith setting and change it from Auto to 20
Save this, and once done, test and tell me if the printer now works correctly please.
I can also do these steps for you, and have made a request via Additional Services. This is optional, and if you choose to do this, I can, with your permission, remote into your computer while you watch and do all these steps (and deal with any problems that arise during them) for you. Or if you do not choose to take this service, we can continue here. This is no problem at all. Just let me know please.
Else let me know the results please.