ps1.7.4.2 Orders Going into Wrong Customer Account

[jayjdi]

I'm having an issue where "customer a" places an order and that order will show up in "customer b's" account and will charge both customers a and b, in some cases will overcharge. I have not seen any error messages the only reason I know is that I have customers calling complaining about receiving invoices for items they didn't place, being overcharged or saying orders have been placed in their accounts of items they never purchased. I read some posts of people with similar issues but could not find a resolution. Could the be a database cleaning issue? Any help in this matter will be greatly appreciated.