Commission not fully paid since june 2015

Sir I did a business thro a company in mumbai for my china buyer importing cotton yarn form india; I hv known the china buyer for many years; This mumbai business man after all negotiations on price and our comm % of 1% on FOB value; entered into an MOU on his letter pad accepting our comm remittance once all money for export is recd by him form our china buyer based on LC 90 days condition; This mumbai buyer opened LC thro another company ( an exporter ) ; this exporter recd all the amount on the specified date as per LC the exporter also gave the comm of 1.5 % to the mumbai business man of which 1% was to our account the mumbai business man would never remit our comm on time and after continuous phone calls and mails; remitted almost 50% in 2 installements since my wife was sick The balance 50% amounting to Rs 3.11 lacs are not remitted since last june 2015 inspite of the fact that my wife is undergoing dialysis and very bad health conditions; He had indicated in many emails asking me to come to mumbai and collect the amount after giving him xerox of debit note and pan card I did go for just one day on july 30th by flight but never got a penny in return he also does not pick his phone inspite of repeated calls and mails i hv no other busienss these days and money crunch can ruin our lives and deteriorate my wife's health one dialysis cost us almost Rs 3 to Rs 4000 and she undergoes 2 dialysis a week in chennai I want this man in mumbai to be taught a lesson and my amount remitted ASAP pl advice n mohan