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If the funding type is State and it should be State check that the debit and credit for that charge have two different FAU's. Eg. material bought on a State job by Carpentry from Shop Stores should get charged as the Carpentry shop would get debited and Shop Stores would get the credit.
If the charge is a Miscellanous Service Entry then check the status on the Entry. If status is Active it did not bill because it was not put into status of "Ready for Upload". If status is "FS Uploaded" check the exception report for the specific exception.