No wifi

My gsm can't pickup the wifi signal in the bedroom where the Netgear wifi modem access point is installed. From the Proximus Fibernet modem in the living room I've attached a fiber cable all the way to the bedroom directly into the Netgear modem. This should not have any loss of signal!? But "for a while now" my gsm doesn't pickup the wifi signal anymore? I did try all the steps in the Netgear app. Nothing? In please help. Cordialement