Every now and then it seems I get a tax duplication issue. I ship within Canada so I have all provinces and territory rules setup for my taxes.
After a few purchases, what ends up happening is that the taxes for 1 province will be displayed multiple times and then sometimes display taxes for another province as well.
For the province of Quebec the TPS and TVQ are to be displayed, but for some reason GST-BC and PST-BC are being displayed and showing inaccurate calculations; however the calculations for the TPS and TVQ are actually the correct total.
The other strange issue is that the same break downs are reflected under the Sales order leading me to the Magento database.
If I go into the database and delete all references to TVQ and TPS in (sales_order_tax) then all subsequent orders have the correct break down. Old orders that were not from the province of Quebec (TPS and TVQ) are lost however.
What steps can be performed to keep this from happening?
Is this a known issue?