I am a homeowner in CA and upgrading my home for a pending sale. The GC has done work without a contract agreement and was paid per his invoices..The work in the kitchen was the priority and the GC said s new double oven would really improve the salibility of the home and he just happen to have a new one. We asked if it was same dimensions and would fit..he said yes, ",there would be no problem ". We paid the $1000 and delivered the oven. We measured it and it was not the same dimensions and I called him and told him the oven was to big a cannot work so we'd be returning it and expect refund..he refused and I put a stop payment on the $1000 check. He is now threatening a lien. What is my legal recourse to prevent snd/or remove this fraudulent claim?