There is technically no time frame for an insurance company to settle a claim. While the insurance company must act in good faith and respond in a reasonable amount of time, there are no strict timelines. Typically, if an insurance company is dragging their feet or refusing to respond timely, you will need to file a lawsuit.
If the insurance company is found to have acted in bad faith, the insurance company may be liable for a verdict amount in excess of the policy limits. Bad faith is a complicated area of the law and you should always consult with an attorney regarding these types of claims. Bottom line is that if the insurance company wont play fair, you need to file a lawsuit to hold them accountable.