It's quite possible that part of what you are thinking exceeds the $24k is state and local taxes(SALT). SALT is capped at $10k total because of tax reform. Also, if you're claiming mortgage interest and any of it was home equity loans that were not used to buy, build, or improve your home, that interest is not deductible.
These are the two most common reasons that people think they should itemize this year, but end up taking the standard deduction. Please advise if this is not your issue.