Problem using Self signed certificate with NGINX

Hi, I face an issue and I am desperate, I don’t know where to look anymore. I want to have an https connection to my nextcloud. I don’t want it to be open to the internet, so I don’t want a domain name. If I type https://192.168.1.100 it gives me ERR_SSL_UNRECOGNIZED_NAME_ALERT

Here is what I’ve done so far :
-I installed Nextcloud :

i changed my casaos UI port to 90 (not in conflict wirth port 80 of NGINX)

-I installed NGINX :

-I created a certificate through the command “openssl req -x509 -nodes -days 3650 -newkey rsa:2048 -keyout nextcloud.key -out nextcloud.crt” and putting the static IP of my CasaOS server as CN. If I type openssl x509 -in nextcloud.crt -text -noout | grep “Subject: CN =”
Then I got
Subject: CN = 192.168.1.100

On NGINX UI, I created a Proxy Host :

I imported the certificate and set up the proxy host to use it like this :

On a client machine, when I type

openssl s_client -connect 192.168.1.100:443 -servername 192.168.1.100 -showcerts

It gives me :

CONNECTED(00000180)

Certificate chain
0 s:CN = 192.168.1.100
i:CN = 192.168.1.100

-----BEGIN CERTIFICATE-----

i don’t give the certificate

-----END CERTIFICATE-----

Server certificate
subject=CN = 192.168.1.100
issuer=CN = 192.168.1.100

No client certificate CA names sent
Peer signing digest: SHA256
Peer signature type: RSA-PSS
Server Temp Key: X25519, 253 bits

AND SO ON…

So it seems NGINX is exposing the right certificate.
I tried to install the certificate on windows
I purged the domain security policies for 192.168.1.100
I tried with nextcloud client (give the error error:0A00458:SSL routines::tlsv1 unrecognized name)
I tried on several machines

I am not an expert on this subject, and any guidance is really appreciated!!

Thank you in advance and sorry for long post, I wanted to give everything I did.