When authorized users go into a Business Partner to view credit card
information there are times where the information is not populated, but
it is in the system. After a few minutes you can go back to the same
screen and you can find the information you were looking for. There has
also been an issue of going from one BP to the next and seeing the
information from the previous BP.
It sounds more like an index issue on your database. I would suggest creating a maintenance schedule in SQL and running it one evening. Start with just an index rebuild and see if that solves the problem. Ensure you run a backup before running the maintenance or include the backup in the maintenance run and set it as first in the order.