Why route through the oVPN client on Mikrotik may not be available to Mikrotik clients?

Question

openvpn

There is a Mikrotik RB3011UiAS router with firmware 6.42.4 (and OpenVPN package 6.42.4). The router distributes the Internet. There is a Debian server with OpenVPN, everything is configured, traffic is going correctly.
Mikrotik has an OpenVPN client configured. There is a connection.
I write the address 173.194.222.139 into the Mikrotik routes:

I do a trace from Mikrotik - everything goes right:

If I do a trace from a client (Mac OS) connected to Mikrotik, then the packets are lost on the router and do not go further.
Checked Firewall, MTU;
Tell me where to dig

Answer 1

solved the problem. it was necessary to add masquarding to the firewall

Answer 2

Does Debian know the way to Mikrotik clients? The ping reaches him, but he does not know where to answer