Expression value resets to zero every time i select anoother track and come back

Using my touch fader on my midi keyboard ;native instruments s61; i adjust the expression(midicc 11 ) value. This value resets to zero every time i select another track and come back to it. So the vst becomes silent.
This happens only while using cubase. I don’t have a similar issue while using my other DAW. So i can say that it is not the midi controller or the vsts.
Any idea about the possible reason?