Unable to connect to the remote environment – Integration environment

We have been testing the eRS and PDS FHIR APIs in integration environment for a few weeks and then it stopped. I have been trying to get some help from the ITOC team but not having much luck.
This looks like a networking issue but again not sure what could have caused it when it was working until the 1st week of February. Please see the attached image.
Is someone else is experiencing or similar problem and got any ideas how to resolve this please?

Hi Mustansar,

Thanks for getting in touch.
The team have advised that “this is a local connectivity problem. We’ve spoken to Mustansar already and advised him of this. He needs to speak to his CNSP (consumer network service provider).”

Have you attempted this yet?