Routing problem

Hi
I have net like on picture net.jpg.
Main mikrotik (MT1.jpg) is used like a gateway, VPN server, DNS …
I have one more mikrotik in net MT2 linked to MT1, and AP (10.50.6.130) linked to MT1.

As a client I connect to the net thru AP-10.50.6.130.

Now, my problem is:
I connect with MT-client (10.42.6.254) to the net, ping 10.1.6.250 is OK, VPN is OK .

I cant access/ping 10.1.0.10 (MT2) from MT-client ??? (ping from MT1 is OK)

Plz, help with routing.

Tnx
NET.jpg
MT1-setup.jpg
MT3-client.jpg

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