Go client handler throwing 500 server error metric consistency issue

I am instrumenting application metrics using the prometheus go client.
I am using the prometheus handler to expose the metrics.

Blockquote
import (

github.com/gofiber/adaptor/v2
github.com/prometheus/client_golang/prometheus/promhttp

)

func MetricsRoutes(api fiber.Router) {

api.Get(“/metrics”, adaptor.HTTPHandler(promhttp.Handler()))

}

On scrape from prometheus, the target starts throwing 500 server error after a few scrapes. This happens only in some environments.
when i tried to hit the /metrics endpoint, i got the following error.
<metric_name> was collected before with the same name and label values

I understand that the go client is throwing it while checking for metric consistency but no clue of why its happening? It works fine in my local environment