Insurance is meant to cover sudden and accidental occurrences. It does not cover the cost of damages due to lack of maintenance. Part of the cost of home ownership is the cost of maintaining it and repairing sections of it as it ages.
Your roofing shingles have a finite life span and need to be replaced before this period expires. Periodically check your roof for worn, broken or curled shingle tabs. Make any necessary repairs immediately to prevent water from entering through a leaky roof. Water damage through a leaky roof due to failure to maintain the roof shingles is not covered by your policy.