Were your Credit Card limits decreased ? if so, and your utilization increased because of the limit decrease, this will drop your score. Any accounts with "age" closed by your or issuer ?

Bought a home 2 1/2 years ago and my score was XXX which gave me the best rate possible. 2 1/2 years later we are seeking to refinance, there have been no changes, additions, deletions, auto loan, 1 car loan was paid off, but nothing negative or new and my credit score has dropped????