Disable immobilizer Twingo 2001

Hello I’m new here. I have already tried the search engine but found nothing suitable. I have a problem with a Twingo Bj 2001, 1.2l 16v. With the Twingo the immobiliser can sometimes not be deactivated. Now I was in a free workshop. There I was told I had to go to Renault and I need a new immobiliser that would cost about 1000€. Now my question I can not simply permanently deactivate the immobiliser? Or is the repair really so te uer? I find my 1000€ stuck in such an old car too much. Thanks already Steffen