Money deducted ********ly

2019 my uncle changed companies and his monies were paid out with some money deducted from his oension fund and reason was old mutual taxed the money and it wa spaid ro SARS. In 2020 we find out old mutual super fund deducted the money but never paid SARs as a results my uncle owes. We have called and we are being called and issue has not been resolved. Aomeone named Seal Titus as admitted to the money beinh deducted but refuse to send prove of payment so we can submit to SARS. We would like to get help regarding the issue and possibly getting the money back so SARs can be paid.