某市登记机构询问:我市中级人民法院在一起民事诉讼案件中做出判决,认定某单位为第三人担保的抵押合同无效。现该判决书已发生法律效力,抵押人要求我单位注销已办理的抵押登记。但是法院在判决书中并没有撤销抵押登记,抵押权人也不愿意交出抵押登记证书。在这种情况下,我们是否可以受理?如果可以, A municipal registration agency asks: Our city Intermediate People’s Court made the judgment in a civil lawsuit case, finds that the mortgage contract guaranteed by a unit as a third party is invalid. Now the verdict has taken legal effect, the mortgagor asked me to write off the registration of the mortgage has been handled. However, the court did not withdraw the mortgage registration in the judgment and the mortgagee did not want to surrender the mortgage registration certificate. In this case, we can accept? If you can,