nginx server and ssh stop responding - nginx

Question

I have a running Flash server on gunicorn under nginx on Raspberry pi zero.
My problem is the raspberry sometime go to sleep a cupe of minutes and server can not be reached and ssh do not work anymore.
So i desable the pi power save with this: sudo iw dev wlan0 set power_save off.
And it's better, but because having issue with 413 Request Entity Too Large i set client_max_body_size to my nginx config file.
But now it's worse, the 'sleep' happen more frequenly, sometime i have to reboot.
This my reverse-proxy.conf:
server {
listen 80;
listen [::]:80;
server_name localhost;
return 301 https://$server_name$request_uri;
}
server {
listen 443 ssl;
listen [::]:443 ssl;
ssl_certificate /etc/ssl/certs/selfsigned.crt;
ssl_certificate_key /etc/ssl/private/selfsigned.key;
error_log /var/www/flask/nginx.log debug;
ssl_dhparam /etc/nginx/dhparam.pem;
location / {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header HOST $http_host;
proxy_pass http://127.0.0.1:8080;
proxy_redirect off;
}
location /upload {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header HOST $http_host;
proxy_pass http://127.0.0.1:8080;
proxy_redirect off;
client_max_body_size 200M; # file needed to upload is just a big image around 1m
}
# increase timeout , 300s, 1d, default: 60s
fastcgi_read_timeout 1d;
proxy_read_timeout 1d;
}
This is the last lines on my nginx log file after 'sleep'.
2021/03/13 21:44:18 [debug] 8220#8220: *445 reusable connection: 1
2021/03/13 21:44:18 [debug] 8220#8220: *445 event timer add: 3: 65000:7060228
2021/03/13 21:44:38 [debug] 8220#8220: *445 http keepalive handler
2021/03/13 21:44:38 [debug] 8220#8220: *445 malloc: 018D46F0:1024
2021/03/13 21:44:38 [debug] 8220#8220: *445 SSL_read: -1
2021/03/13 21:44:38 [debug] 8220#8220: *445 SSL_get_error: 5
2021/03/13 21:44:38 [debug] 8220#8220: *445 peer shutdown SSL cleanly
2021/03/13 21:44:38 [info] 8220#8220: *445 client 192.168.1.72 closed keepalive connection (104: Connection reset by peer)
2021/03/13 21:44:38 [debug] 8220#8220: *445 close http connection: 3
2021/03/13 21:44:38 [debug] 8220#8220: *445 SSL_shutdown: 1
2021/03/13 21:44:38 [debug] 8220#8220: *445 event timer del: 3: 7060228
2021/03/13 21:44:38 [debug] 8220#8220: *445 reusable connection: 0
2021/03/13 21:44:38 [debug] 8220#8220: *445 free: 018D46F0
2021/03/13 21:44:38 [debug] 8220#8220: *445 free: 00000000
2021/03/13 21:44:38 [debug] 8220#8220: *445 free: 018F56F0, unused: 8
2021/03/13 21:44:38 [debug] 8220#8220: *445 free: 01933360, unused: 120
kermel log (/var/log/syslog):
Mar 13 22:48:09 raspberrypi rngd[270]: stats: Time spent starving for entropy: (min=0; avg=0.000; max=0)us
Mar 13 22:58:08 raspberrypi systemd[1]: session-10.scope: Succeeded.
Mar 13 23:17:01 raspberrypi CRON[25098]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Mar 13 23:44:19 raspberrypi dhcpcd[385]: wlan0: hardware address 00:00:00:00:00:00 claims 192.168.1.64
Mar 13 23:44:21 raspberrypi dhcpcd[385]: wlan0: hardware address 00:00:00:00:00:00 claims 192.168.1.64
Mar 13 23:44:21 raspberrypi dhcpcd[385]: wlan0: 10 second defence failed for 192.168.1.64
Mar 13 23:44:21 raspberrypi avahi-daemon[260]: Withdrawing address record for 192.168.1.64 on wlan0.
Mar 13 23:44:21 raspberrypi avahi-daemon[260]: Leaving mDNS multicast group on interface wlan0.IPv4 with address 192.168.1.64.
Mar 13 23:44:21 raspberrypi dhcpcd[385]: wlan0: deleting route to 192.168.1.0/24
Mar 13 23:44:21 raspberrypi dhcpcd[385]: wlan0: deleting default route via 192.168.1.254
Mar 13 23:44:21 raspberrypi avahi-daemon[260]: Interface wlan0.IPv4 no longer relevant for mDNS.
Mar 13 23:44:21 raspberrypi dhcpcd[385]: wlan0: rebinding lease of 192.168.1.64
Mar 13 23:44:21 raspberrypi dhcpcd[385]: wlan0: probing address 192.168.1.64/24
Mar 13 23:44:26 raspberrypi dhcpcd[385]: wlan0: leased 192.168.1.64 for 86400 seconds
Mar 13 23:44:26 raspberrypi avahi-daemon[260]: Joining mDNS multicast group on interface wlan0.IPv4 with address 192.168.1.64.
Mar 13 23:44:26 raspberrypi avahi-daemon[260]: New relevant interface wlan0.IPv4 for mDNS.
Mar 13 23:44:26 raspberrypi avahi-daemon[260]: Registering new address record for 192.168.1.64 on wlan0.IPv4.
Mar 13 23:44:26 raspberrypi dhcpcd[385]: wlan0: adding route to 192.168.1.0/24
Mar 13 23:44:26 raspberrypi dhcpcd[385]: wlan0: adding default route via 192.168.1.254
Mar 13 23:48:09 raspberrypi rngd[270]: stats: bits received from HRNG source: 180064
Mar 13 23:48:09 raspberrypi rngd[270]: stats: bits sent to kernel pool: 123584
Mar 13 23:48:09 raspberrypi rngd[270]: stats: entropy added to kernel pool: 123584
Mar 13 23:48:09 raspberrypi rngd[270]: stats: FIPS 140-2 successes: 9
Mar 13 23:48:09 raspberrypi rngd[270]: stats: FIPS 140-2 failures: 0
Mar 13 23:48:09 raspberrypi rngd[270]: stats: FIPS 140-2(2001-10-10) Monobit: 0
Mar 13 23:48:09 raspberrypi rngd[270]: stats: FIPS 140-2(2001-10-10) Poker: 0
Mar 13 23:48:09 raspberrypi rngd[270]: stats: FIPS 140-2(2001-10-10) Runs: 0
Mar 13 23:48:09 raspberrypi rngd[270]: stats: FIPS 140-2(2001-10-10) Long run: 0
Mar 13 23:48:09 raspberrypi rngd[270]: stats: FIPS 140-2(2001-10-10) Continuous run: 0
Mar 13 23:48:09 raspberrypi rngd[270]: stats: HRNG source speed: (min=101.599; avg=254.741; max=920.244)Kibits/s
Mar 13 23:48:09 raspberrypi rngd[270]: stats: FIPS tests speed: (min=924.206; avg=3071.971; max=9096.996)Kibits/s
Mar 13 23:48:09 raspberrypi rngd[270]: stats: Lowest ready-buffers level: 2
Mar 13 23:48:09 raspberrypi rngd[270]: stats: Entropy starvations: 0
Mar 13 23:48:09 raspberrypi rngd[270]: stats: Time spent starving for entropy: (min=0; avg=0.000; max=0)us
Mar 13 23:57:38 raspberrypi dhcpcd[385]: wlan0: part of Router Advertisement expired
Edit:
It's possible the problem come from my computer or the pi filtering my compyter ip, because sometime i can ssh or reach the http server from my Android phone which is in the same network, but no internet or firewall(ESET antivirus) problem in my computer.