The answer to 'my shingles is failing' is that your roof shingles are likely deteriorating and need repair or replacement. Common causes include weathering, age, poor installation, or damage from storms. Symptoms include curling, cracking, missing granules, or leaks.
If the damage is limited, you may be able to patch or replace a few shingles yourself. However, if a significant portion of the roof is affected, it's best to call a professional roofing contractor to inspect the roof and provide a comprehensive solution. They can assess the extent of the damage, determine if the entire roof needs replacement, and ensure proper installation to prevent future issues.