getting port 443 after 127226 ms: Couldn’t connect to server

I am integrating the third party api but getting port 443 after 127226 ms: Couldn’t connect to server

GuzzleHttpExceptionConnectException
cURL error 28: Failed to connect to xxxxx.xx port 443 after 127226 ms: Couldn't connect to server (see https://curl.haxx.se/libcurl/c/libcurl-errors.html) for https://xxxxxxxxx/api/v1/service/recharge/recharge/getoperator

this is the full error message i get. I tried contacting the server provider they told me to white list the api ip. I did. but not working. it works fine in the POSTMAN.