Issue Problem with loopback in Plesk with NAT

[ChristosMitsis]

Server operating system version

AlmaLinux 9.6

Plesk version and microupdate number

Version 18.0.69 Update #3

Hello, I have a Plesk server hosted in a Proxmox host. I have forwarded the IP using NAT. The host's /etc/network/interfaces file is like this:

auto vmbr0
iface vmbr0 inet static
address 157.90.XXX.XXX/26
gateway 157.90.XXX.XXX
bridge-ports enp6s0
bridge-stp off
bridge-fd 0
up sysctl -p
post-up iptables -t nat -A PREROUTING -i vmbr0 -p tcp -m multiport ! --dports 22,8006 -j DNAT --to 192.168.69.2
post-up iptables -t nat -A PREROUTING -i vmbr0 -p udp --dport 53 -j DNAT --to 192.168.69.2
post-down iptables -t nat -D PREROUTING -i vmbr0 -p tcp -m multiport ! --dports 22,8006 -j DNAT --to 192.168.69.2
post-down iptables -t nat -D PREROUTING -i vmbr0 -p udp --dport 53 -j DNAT --to 192.168.69.2

auto vmbr_virtual
iface vmbr_virtual
address 192.168.69.1/24
bridge-ports none
bridge-stp off
bridge-fd 0
post-up iptables -t nat -A POSTROUTING -s '192.168.69.0/24' -o vmbr0 -j MASQUERADE
post-down iptables -t nat -D POSTROUTING -s '192.168.69.0/24' -o vmbr0 -j MASQUERADE

The Plesk server is a web, mail and DNS server
From within the VM (the Plesk Server) I cannot curl -I https://website.com (a website hosted inside the VM). I get a connection refused.
Also, inside the websites I have an SMTP mailer plugin that uses the SMTP server of the Plesk. I get connection refused there too.
Also, when I try to access the webmail, when I log in, I get "Connection to storage server failed"

I think that all of that is the same problem. What should I do?