Reliance Jio Infocomm — Didn't pay full refund amount

I ordered and installed Jiofiber at my house which had 100% refund policy for uninstalling but when I request for uninstall of the Jiofiber they issued me a date on which they'll pick up the device but they didn't come.I called many times and they kept issue me date but they never came after 2-3 month they finally came after I again called and complaint but now they didn't refund me full amount because they're saying I didn't return the device before 60 days but in reality they never came and intentionally avoided my uninstall request and it's been 1 year they still didn't give my full amount money.