Non payment of due salary summary suit may be possible

I retired from BSNL Agra on 30.04.2019. I got victim of non payment of salary since May to Sept. 2015 for five consecutive months . Later this non payment turned to unauthorized deduction of Rs 20,000 per month from each further salary. This Unheard victimization reached to 835155.00 with performing my sincere duty. I never got any show cause notice. No disciplinary action ever initiated against me. These acts of BSNL were unilateral. and arbitrary.with abuse of authority. I got no authentic order of salary disentitlement. Numerous requests were made to PGM for stop harassment and to release entitled salary. all gone unresponded. DGM(A) lying hanged assuring release of salary till my retirement but gone deceptive he could not release. I requested PGM on the day of my retirement either to release my due salary 835155.00 or pass an authentic order of salary disentitlement. He accepted nor rejected the claim. He gone deaf. No justification existed.