mobile phones say connected to WiFi but say no internet access router reset

[Keith1]

Router reset and phones have had WiFi cnnection deleated and then reinstalled, on installation it says no "WiFi connection avalable do you sill want to connect " i have connected. the problem first come to my attention two days ago, though my daughter had been complaining of problems with internet connecion earlier in week. A Ipad WiFi connection is working perfectly. The phones are using Tesco system and one phone is working perfectly using a BT system