Hi there and welcome
Can you remove the power to your wifi router and your speakers
Wait 5 minutes, connect the power to the wifi router, wait 5 minutes, connect the power to the speakers and tell me if it is now functioning please.
ok, now whats the make and model of the phone?
connect to an existing system
Power off the kitchen speaker again, then power it on and try to connect to it
It can be as you may have changed the setup.
Rename the correct speaker to the dining room as you had it before, like when you first set it up
Select Manage or Settings > Add a Sonos Component then follow the prompts there
choose auto update apps over Wi-Fi please
ok, now use manage to add the speaker please
ok... so which one are you missing?
Try playing to them
no I cannot
But hold the power button on the phone until the menu shows and choose restart
Then restart and try again please
Can you go to settings, applications manager, then select the Sonos app and select uninstall
Then restart the phone and install it again and tell me if it now works please