Laptops not connecting to wifi range extender

hi there,

Im having issues with my wifi booster, it has always worked perfectly then all of a sudden the internet has stopped working on laptops. It works perfectly on other devices such as phones and a fire tv stick but just says 'connected, no internet' on laptop. 

Ive tried resetting the wifi booster to factory settings and setting up again but this hasnt resolved the problem, can you help?