curl --request POST \
  --url https://api.nh.staging.mum.juspay.net/service2/auth/token/refresh \
  --header 'Content-Type: application/json' \
  --data '
{
  "refresh_token": "<string>"
}
'

{
  "access_token": "<string>",
  "access_token_expires_at": 123,
  "refresh_token": "<string>",
  "refresh_token_expires_at": 123,
  "success": true
}