Collection on unpaid utitlity bill now paid and my score dropped.

I viewed my credit report after a 2 year gap and was shocked to find a collection against an unpaid utility bill. Without the knowledge of negotiations I chased the collection company down and paid of the debt, only to find that my credit score dropped from 705 to 660, by all 3 agencies.
Is there any way I can get this negative info removed from my account after the fact that I paid the bill ?
The collection agency NCO financial wont answer my calls to discuss.
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660 is still a good score and it will increase quickly with new open and current lines of credit. Sometimes a credit score will take a short term hit if a collection gets a new "last activity date" put on the account when a person pays.
It still looks better than having a outstanding non paid collection.
If they will not answer calls then dispute the account
Use the dispute form and say reported incorrectly.
www.oskie.com/credot-dispute.htm
wish