WLAN works with laptop, but not with mobile phone?

Have got a used router for my apartment from my sister, which I have now set to factory settings. I receive with both devices the WLANSIgnal, but the mobile phone is there, Internet may not be available ", I have already looked at the settings on fritz.box, but I can't find anything, how can I have access to my phone? At the beginning it was short, so it should be possible in principle…

You can also set in the Fritz box that the devices can act in the network, but can't access the Internet with the profile…
Take a look through the profiles that you can assign on every device…
If that does not help, reset network settings from the phone…
If other devices funz, that should go too…

I have already deleted the network and reset. That did not work. Delete network settings "is not explicit.

The devices are both the same distance?

Then the reception should be similarly good.

Did you enter an individual SSID - not the cell phone with the same Fritz! Wants to connect box with also not changed standard SSID because the signal is stronger there…

Look at factory settings or reset…
That should be something with network settings…