WiFi and access points

[David Lindgren]

As a beginner I try to connect to wifi using my phone as possible access point.
I found the below code:

from network import WLAN
wlan=WLAN(mode=WLAN.STA_AP)
nets=wlan.scan()
print(nets)
for net in nets:
    print (net.ssid)

and thought it would provide all networks, i.e my phone and my router. But, only my router shows up and I get a message that AP

Traceback (most recent call last):
File "boot.py", line 16, in <module>
ValueError: AP SSID not given
WMAC: 10521C65D52C

The Wifi SSD is in a file pybytes_config.json. There is another settingsfile but I do not know where.

But, shouldn't the SCAN method provide all networks without any SSID settings?