Malindo Air - Non refund of Canceled Air ticket

My self booked air ticket from Cochin to Yangon and back on **thFebruary **** for onward journey to Yangon on ** March **** by flight No OD *** and OD *** and return journey on**th March **** by flight No.OD *** and OD *** with Malindo air .But even before starting my outward journey Air lines re scheduled first portion return journey form Yangon to Kulalampur from**th March to **th march duly keeping second portion of flight from Kulalampur to Cochin on **th March senselessly. After reaching Yangon, on persuasion air line provided a return journey air ticket to Chennai from Yangon on **rd March **** instead of arranging air ticket to Cochin book on **th March ****. Subsequently that ticket also cancelled unilaterally on account of Covid ** Pandemic. But Air line is not willing to refund my unused portion ticket charge instead air line offered only a voucher valued for * Months to use only in their airlines , which is not an acceptable offer to me as I am not a frequent traveler and I may not use this ticket Voucher not even within an year . So I requested the air line to refund the amount in the from Cash instead of Voucher.
For managing the situation undersigned constrained use other option to reach back by home town I had spend an amount of Rs ***** as flight ticket Yangon to Calcutta, Calcutta to Chennai then Chennai to Cochin on **thMarch ****.
I requested the air line to refund my unused portion of air ticket in cash instead of Voucher ,Malindo Air lines not yet consider my request but refused. This act vehement act of Malindo Air create mental agony , financial loss and unnecessary tension which indirectly deteriorate my health during this my old age .