FRER is negative!!!! Help

M 🌈

Can anyone please explain why this keeps happening? I have a history of chemicals due to a high TSH level.. (subclinical hypothyroidism) but I have had multiple faint lines that get darker with the strip tests but they NEVER show on a first response test.

I know it isn’t the strip tests because I have had this happen before and dipped the strips in water to check if they were evaps so confused 😑😑