Cannot access from internal network

Configuration Frontend
1

I have the following configuration;
HA in the internal network using port forward
To resolve names I use Cloudflare DNS and a valid domain name and SSL using the Lets Encrypt

I´m able to login internally only using the local IP but with SSL error, but from the internet I can connect using the valid domain. I could use the domain to access from internal and external normally until 4 days ago.

But now, if I try to connect from the internal network, I can´t access anymore, only by internal IP.

From the internet using the domain name. Works fine.

I already checked everything, and looks right. Anyone has any suggestion?

thank you

2

Changed router? Seems hairpinning does not work anymore.

3

I didn’t change anything.