@k098 wrote:
I noticed while looking at my credit score, that one of my credit cards are not included in the calculation. How can I fix it and include it in there?
That is atypical, but it happens (link below). About the only thing you can do is request that the credit card company report to the bureau (or all three of them) if they're not doing so already.
See https://www.creditkarma.com/credit-cards/i/credit-card-companies-report-credit-bureaus/
Note that in the unlikely event you actually have a debit card, be aware that the information is generally not reported.