Check your firewall. By default, if you didn’t have any, it would work (assuming 172.29.29.2/30 is connected to vlan 6 and 172.30.30.2/30 is connected to vlan 7). It’s what router does, it routes anything it can. If it doesn’t work, it’s probably some firewall rule blocking it, or configuration mistake somewhere else.
And you may need to check the Layer2 Switch in the middle too, i’d check if the plans are properly tagged and the port configuration is correct (between trunks & access)
There should be no further action on the Mikrotik needed (assuming no restrictive firewall rules). It should show two routes with flags DAC for both 172.30.30.0/30 and 172.29.29.0/30
When routing traffic your source device need a route to your destination and your destination device needs a route back to the source.
So your host on 172.29.29.2 must have a route added for 172.30.30.0/30 with gateway=172.29.29.1 - and likewise the 172.30.30.2 host must have a route to 172.29.29.0/30 with gateway=172.30.30.1