C6300 - Can NOT connect phones or printer after changing password.

I recently changed my password from the default "password" to a new PW by means of changing the PW to my C6300 gateway/router via my PC. Since then I have been unable to connect my phones or printer to the router.

I have a Kindle Fire that I never changed the Network PW on, that remains connected to my network.

My PC is able to connect to my printer, but my printer is not able to connect to my network and "speak" to my PC. When I try to connect my printer I either get an error of "Wrong PW" or "Failed to Connect" When I try to connect to my router with my phones I get an indication that my Network is disabled.

My phones worked without changing the password for a few days but then lost the connection and I am unable to reconnect to the network.

My Network shows as available on my phones and printer, but I am not able to connect to it :-(

I assume that changing my gateway/router PW on my PC also changed My PC's connection PW to the gateway.

What's the problem?????  Am I doing something the wrong way ???