Dear,
please note that Sentinel Hub has no affiliation with Copernicus Open Access Hub, so we cannot provide any specific advice.
That said, this might be related to the phase out of the Hubs. We recommend to make use of the newly established Copernicus Data Space Ecosystem:

Copernicus Data Space Ecosystem

Copernicus Data Space Ecosystem | Europe's eyes on Earth

Welcome to the Copernicus Data Space Ecosystem, an open ecosystem that provides free instant access to a wide range of data and services from the Copernicus Sentinel missions and more on our planet’s land, oceans and atmosphere.

Perhaps worth to check the guide:

Copernicus Data Space Ecosystem

Accessing Sentinel mission data via the new Copernicus Data Space Ecosystem APIs

How to upgrade your EO workflows using the new Copernicus Data Space Ecosystem.Written by William Ray and Andras Zlinszky, Sinergise

I see! This is super helpful. Many thanks and much appreciated.