Incorrectly posted cancelled Billing doc.
Previously, our user created and posted a Billing doc. on 29.08.2014, i.e. Billing date in Billing doc., Doc. date & Posting date in the relevant accounting doc. were same as this date.
Then, our user was requested by another Finance user to create a Cancel Billing doc. with ref. to the above Billing doc. on 24.12.2014. In our "SD - Billing Type" setting, there is no posting block for our Cancel Billing doc. so it can be posted to Finance & cleared automatically as long as the referred Billing doc. was also posted to Finance before. However, that Cancel Billing doc. could NOT be posted to Finance as the Posting period of Aug 2014 was NOT opened. When our user found this problem, it was already on 07.01.2015. The Billing date of the Cancel Billing doc. was same as that of the above Billing doc., i.e. 29.08.2014. Then, our user tried to change the Billing date from 29.08.2014 to 07.01.2015 in the Cancel Billing doc. Then, it could be posted to Finance but the Doc. date & Posting date in the relevant accounting doc. were different, i.e. "Doc. date = 29.08.2014" & "Posting date = 07.01.2015".
Our another Finance user originally wanted the Doc. date & Posting date in this accounting doc. of the Cancel Billing were the same as "29.08.2014". Now, the Cancel Billing doc. cannot be cancelled or revoked and the Posting date cannot be changed in the accounting doc. Could you advise whether there is any appropriate solution to solve this problem ?