Over your limit

As a family of 2, I find it difficult to believe we have exceeded our monthly internet limit. We have 3 tvs and typically use our unlimited cell data for our phones. I received one notification in 2021 that we went over and then nothing (we didn’t change anything) until Dec and now Jan. Based on reviewing this same complaint by many comcast customers, this is not isolated and may be a flaw which is adversely impacting customers.