H1b Fee refund in case of approved but not stamped

Hi ,

My H1b filed this year and it got approved in Oct. For the same I have signed a bond for 2 years. Now my employer does not have any project to send my onsite , so they are not stamping my H1B. So my question is, in case if my employer ask for cancel of H1B, will they get return of fee paid for H1B which got approved.

In case i break bond now, do i need to pay full H1B filing fee or only some part of it? Please confirm, it is urgent.