generating variants does not work

I am trying to generating variants but it does not work. debug log shows below.

SELECT * FROM content_shop_products WHERE productID=1 AND productDeleted IS NULL LIMIT 1
[2] SELECT o.* FROM content_shop_options o, content_shop_product_options po WHERE o.optionID=po.optionID AND po.productID=1 AND o.optionDeleted IS NULL ORDER BY optionPrecendence ASC
SELECT pov.prodoptID, pov.optionID, pov.valueID, o.optionTitle, ov.* FROM perch2_shop_product_option_values pov, perch2_shop_options o, perch2_shop_option_values ov WHERE pov.productID=1 AND pov.optionID=o.optionID AND pov.valueID=ov.valueID AND o.optionDeleted IS NULL AND ov.valueDeleted IS NULL AND o.optionID='1' ORDER BY o.optionPrecendence ASC, ov.valueOrder ASC
Invalid query: SQLSTATE[42S02]: Base table or view not found: 1146 Table 'localdb.perch2_shop_product_option_values' doesn't exist
SELECT pov.prodoptID, pov.optionID, pov.valueID, o.optionTitle, ov.* FROM perch2_shop_product_option_values pov, perch2_shop_options o, perch2_shop_option_values ov WHERE pov.productID=1 AND pov.optionID=o.optionID AND pov.valueID=ov.valueID AND o.optionDeleted IS NULL AND ov.valueDeleted IS NULL AND o.optionID='2' ORDER BY o.optionPrecendence ASC, ov.valueOrder ASC
Invalid query: SQLSTATE[42S02]: Base table or view not found: 1146 Table 'localdb.perch2_shop_product_option_values' doesn't exist

I don't know why it is trying to search for "perch2_" prefix. I am using custom prefix, so I am guessing somewhere "perch2" is hardcoded.