Unclaimed funds

My mother have unclaimed funds with Oldmutual.She was told that Oldmutual will not reliese the funds due to her id numbers are not the same reason being the first id before marriage was done before 1994 which was a dompass and her marriage id was done after 1994..Old mutual contacted homeaffairs and this was explained to them on behalf of my mother and they couldnt issue a written confirmation as this is a known matter that a dompas id no is not the same as the new id issued after 1994.How can we get assistance