Hi,
From nothing something is blocking my lan network, we didn't move anything and can't connect to my customers routers. I added a firewall filter rule to free everything and didn't work.

Can somebody helpme remotelly please.

I can connect to everything without any problem, RB, CPEs, VPN, Switches, just my lan network is blocked. Restart the RB, upgrade version and nothing work.

Solution:

The problem was that all my network is bridged. Only at the end we put a router, could be TP-Link or airgateway.
One of the airgateways was cloning our router's gateway and was creating an arp cycle or loop (something like that).
Thanks for the help to @CelticComms and we could locate the error. So, we blocked the client's CPE that has the airgateway and our network is back.

Best regards to everyone.

Is the LAN interface showing an active link? Does torch show any activity?

Thank for your reply.
Yes, ether1 is active, and torch show some activity. some clients can navigate, if a restart the router other clients navgite is something randome.

This happened from one minute to another. Allready restarted the router, reset to default configuration and restore yesterday backup.

Any unusual CPU load or WAN load? Any pattern connecting those who can connect and those who cannot?

No, CPU is perfect 0 to 3%, WAN is working like a charm. Is like if a have a filter rule blocking that network.
Can you help me via teamviewer?

I cleared DNS cache, rebooted all CPEs, tried everything.