Errors on uploading rates

Hi.
I am having errors uploading rates.
in line 351 of rates_model.php there is a reference to "old_cost" which seems to find its way into the database query, and this is where it fails.

The query generated is:
INSERT INTO routes (pattern, comment, connectcost, includedseconds, cost, init_inc, inc, precedence, last_modified_date, pricelist_id, trunk_id, reseller_id, creation_date) VALUES
('^467677.*','Sweden Mobile Telia','0','0','0','60','60','','2017-09-11 07:32:17','4','1','0','2017-09-11 07:32:17') ON DUPLICATE KEY UPDATE old_cost = IF(VALUES(cost) != cost,cost,old_cost), effective_date = IF(VALUES(cost) > cost,'',(IF(VALUES(cost) < cost,'',effective_date))), comment=VALUES(comment), connectcost=VALUES(connectcost), includedseconds=VALUES(includedseconds), cost=VALUES(cost), init_inc=VALUES(init_inc), inc=VALUES(inc), last_modified_date=VALUES(last_modified_date), status=IF(VALUES(cost) = '-1','1','0')

Any feedback would be appreciated.