Soft switching flyback converter is not working in boost mode.

Sir..

I have designed a soft switching flyback converter and simulated in MATLAB. But it is not working as closed loop.
It is not working in open loop especially boost mode.

What I meant by not working in open loop is that it doesn't give the required output for which duty ratio its designed.
In closed loop it doesn't give the reference voltage as output.

Is that because of the problem with transformer or anything else?

Is there any problem that a flyback converter can't work in boost mode?

My input is 24V. Load is 12V 24W

Please help..

Thank you