Can't access services on the same network but works from the outside

I'm trying to fix a problem with my Raspberry Pi3 running Raspbian. I have installed MotionEye and Hyperion on it, enabled all neccesary ports in my router but the services could be accessed for 5-10 mins after a reboot from local and public ip and after only from the outside of my network. I'm trying to fix it but I got stuck. So, I set a static IP for the Raspberry which is 192.168.1.7 , enabled ssh / motioneye / hyperion ports in the router for that ip. Connecting from the outside of my network on the public ip 92.xx.xx.xx:port , works fantastic. If I am connected on the same network as the Raspberry, 92.xx.xx.xx:port doesn't work, even 192.168.1.7:port doesn't work. The weird thing is, if I'm rebooting the pi, it works fantastic for 5 to 10 minutes, and then suddenly I can't connect anymore on the local network, but still works ok from the outside. Pinging local ip 192.168.1.7 returns:

teo@teo-E6230:~$ ping 192.168.1.7
PING 192.168.1.7 (192.168.1.7) 56(84) bytes of data.
From 192.168.1.16 icmp_seq=1 Destination Host Unreachable
From 192.168.1.16 icmp_seq=2 Destination Host Unreachable
From 192.168.1.16 icmp_seq=3 Destination Host Unreachable
From 192.168.1.16 icmp_seq=4 Destination Host Unreachable
From 192.168.1.16 icmp_seq=8 Destination Host Unreachable
From 192.168.1.16 icmp_seq=9 Destination Host Unreachable
From 192.168.1.16 icmp_seq=10 Destination Host Unreachable
^C
--- 192.168.1.7 ping statistics ---
10 packets transmitted, 0 received, +7 errors, 100% packet loss, time 9206ms
pipe 4

It looks like the IP that returns while pinging, it's actually my laptop's local IP

wlp2s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
inet 192.168.1.16  netmask 255.255.255.0  broadcast 192.168.1.255
inet6 fe80::226c:cd03:4c3c:d34  prefixlen 64  scopeid 0x20<link>
ether 00:22:fb:bb:80:62  txqueuelen 1000  (Ethernet)
RX packets 47481  bytes 54732580 (54.7 MB)
RX errors 0  dropped 586  overruns 0  frame 0
TX packets 29537  bytes 4539008 (4.5 MB)
TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

an anyone please help and guide me?

can you post route -n from both the pi (.7) and the laptop (.16) ?

route -n from my laptop:

 Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.1.1     0.0.0.0         UG    600    0        0 wlp2s0
192.168.1.0     0.0.0.0         255.255.255.0   U     600    0        0 wlp2s0

** route -n ** from the Raspberry Pi:

>  Kernel IP routing table
>  Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
>  0.0.0.0         192.168.1.1     0.0.0.0         UG    303    0        0 wlan0
>  192.168.1.0     0.0.0.0         255.255.255.0   U     303    0        0 wlan0

I assume your router has a 92.* public WAN and 192.168.1.1 LAN. There must be a setting in your router, pi should be able to ping laptop and vice versa. Can either pi or laptop ping 192.168.1.1 ?

Yes. For 192.168.1.1 I get responses from laptop and from the pi. Both of them can ping 192.168.1.1 . Pinging the pi from my laptop works for 10 minutes max after a reboot of the pi. After this time, the pi becomes unreachable from my local network.

Do you have another power supply for the pi to test?
if the power supply is failing, the first thing turned off is ethernet.

But then it shouldn't accept connections from outside of the network. If the power supply fails, it should be unreachable from everyone. But still, I can access it if I'm not connected to the same network.

can you reboot your router and test again?

I did that... It works great for the first 10 minutes and then no local access to the Pi.

iwconfig on the pi, do you have power management ON? maybe the pi sensing no activity turns the network off. How did you setup the pi (and laptop) having a static ip since both of them use the wireless device (wlp2s0 for laptop, wlan0 for pi). Is there a DHCP server on the router?

Power management is on. The router has a setting to set a static ip on the MAC address.

Iwconfig on the pi:

pi@pi3:~ $ sudo iwconfig
wlan0 IEEE 802.11 ESSID:"Telekom-2.4"
Mode:Managed Frequency:2.432 GHz Access Point: 18:90:D8:94:FC:56
Bit Rate=65 Mb/s Tx-Power=31 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:on
Link Quality=50/70 Signal level=-60 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:199 Invalid misc:0 Missed beacon:0

eth0 no wireless extensions.

lo no wireless extensions.

pi@pi3:~ $

Even so, why it’s still accesible from the outside of the network on the public IP. Power management should turn off the entire internet access, not only local.

Wiped the SD card, imaged a clean install of Raspbian, reinstalled motioneye and hyperion and now it works as it should. Topic closed! Didn't know exactly what the issue was, but it works ok after a complete wipe and clean installation.