I agree with Mr. Wright but will give a slightly different answer. The deadline to take care of the problem is whatever deadline you set. You should write to them and demand this gets done within a reasonable amount of time and then have a dialogue about it getting completed. If it doesn't happen, then your remedy is to sue.
Outside of your ability to timely file a lawsuit, there is no real answer as to 'how long' someone has to repair damage they caused your property. With some more details I would be able to give you a more precise answer and try to give you some advice in moving forward.
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