Like "Could your test strips have gone bad? Here are a few rules for them: Protect the test strips from damage that might change the results. Do not touch the test area of the strip or allow it to touch the table. Protect the test strips from moisture, direct sunlight and heat. Keep the test strips in a cool, dry place but do not store in the refrigerator. Do not remove desiccant (white packet in bottle). Replace the bottle cap promptly and tightly. Check the expiration date on your test strips. Do not use if the date has passed. Use the strips within 6 months after first opening the bottle. Do not use test strips that have discolored. Other than that, sorry, I cant be of any help. Good luck. "