Outstanding pension fund pay out .

My father passed away in 2018 April, he worked for Durban transport ( retrenched) and was paid a pension fund of R2875.48 monthly. My mother submitted all the required documents for her to receive the monthly pay outs. To her dismay in 2019 November she only received R2875.48*2 and has since been getting that amount to date. Now what i would to know from Alexander Forbes what happened to the outstanding amount of R 51 758.4 ( R2875.48 *18 months). We have been making endless calls to you and everyone promises to resolve this issue and no one does!! do you know much airtime and energy we have used to resolve this and NO ONE IS ASSISTING...We went to the Umhlanga branch they advised that we should contact the Sandton branch as they unable to help... we have been calling Phumzile on : ***, Devika *** and Zahier on *** and they are not assisting.. To you maybe this money is just a drop in the ocean but to my Mother it will help her a lot.. Can someone please investigate and assist the soonest