Dear all.
I replaced the damaged switch. Installed a new switch - Cisco Nexus 3064, everything works fine except one VLAN on which QinQ worked. My switch only transit vlan. Thus, Nexus contains only have trunk configuration. However, QinQ does not pass to the customer. I am still approaching the cause in Jumboframe, but despite the correct settings it does not work. Nexus can see the MAC addresses of the sending page, but the target switch can not see these addresses.
What could be the reason ?