Midi recording vst synths in OT

Ive linked my ableton as an external synth in a midi thru chain.

Here is the problem…

I have a SL mk 2 connected via midi out to the midi in to OT, and when the computer is of i can record as expected into OT midi sequenser with the SL.
At the chosen midi ch. witch correspond to my outboard gear

When i launch ableton and load a vst and choose the right midi channel in my SL and my OT and ableton, then I can not longer record into OT on the midi seq.

My OT can play the vst and if I place trigs the vst respond.

am I missing something? U shold bee able to do this right?