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to both users. my short term fix is turning your wifi off on your phone(wait 30 seconds) and then turn it back on. if the wifi does not turn off on your phone. or that fails to fix the problem. put your phone in airplane mode. wait 30 seconds. turn airplane mode off then turn your wifi back on.
you shouldnt need to do anything to your router.
at my house everyone connects fine. my wifes phone just wont connect to wifi. so that is what i do to get it to connect. im trying to find a more permant solution.