去年开了家小餐馆，用自己个人担保签了十年合约，现在因为多种因素做不下去了，我已经找好了买家，房东也同意把租约过户给买家，房东很多苛刻的条件我也只能接受，今天收到了房东的新合同，里面忽然多了这句话，Assignor hereby agrees to remain liable as a guarantor of all obligation of tenant under the Lease both before and after the date hereof, through the principal and any extended term. The exercise by Landlord of any remedy against Assignor shall not preclude Landlord from the exercise of the same or other remedies against Assignee at the same or different times.，是不是我的担保人身份就算把租约转给买家了，也不能解除？我该怎么办？怎么和房东交涉？
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