Not able to get x-forwarded-for header from mozilla to API gateway

Hi ,

i am using kong version 1.4.0. i had set up Apllication load balancer infornt of API gateway. when i access kong API gateway from mozilla with loadbalancer, i am not able to receive x-forwarded-for header.It works fine with chrome, safari & Edge.

i am using below function to receive headers
local get_headers = ngx.req.get_headers

Please help me to resolve this

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