I have the exact same problem. Don't know what to do.
AT+CIFSR
+CIFSR:APIP,"192.168.4.1"
+CIFSR:APMAC,"5e:cf:7f:90:7c:75"
+CIFSR:STAIP,"0.0.0.0"
+CIFSR:STAMAC,"5c:cf:7f:90:7c:75"
OK
AT+CIFSR
+CIFSR:APIP,"192.168.4.1"
+CIFSR:APMAC,"5e:cf:7f:90:7c:75"
+CIFSR:STAIP,"0.0.0.0"
+CIFSR:STAMAC,"5c:cf:7f:90:7c:75"
OK
DHCP TIMEOUT
WIFI DISCONNECT
WIFI CONNECTED
DHCP TIMEOUT
WIFI DISCONNECT
WIFI CONNECTED
DHCP TIMEOUT
WIFI DISCONNECT