I left company "A" on july 5th due to poor HR policy poor salary joined company 'B' on 12th july without releiving letter than after one month, company 'A' provided releiving letter on AUGUST 21 but mentioned last working day as august 21, which i never checked after 2 years i got opportunity in company 'c' where company 'C' not accepting due to overlap in dates and saying dual employment ,but i did not receive any salary from company 'A' for month of july or august, but company 'A' is not correcting my releiving letter as july 5th leaving day, please tell me how to overcome the situation so that i could get opportunity in company "C".