Hi @droche, we plan on sunsetting the Get deal pipelines API sometime in the future in favor of the more flexible CRM pipelines API, but that change shouldn't have happened yet. This changelog update should go over the plans here, but as per the last section "The existing Deal Pipelines API endpoints will continue to function as usual to maintain backwards compatibility."
Taking a look at the URL you sent over, it looks like there are two forward slashes after hubapi.com which isn't valid. Can you check to see if that's a typo here or if your code actually includes that? If not, can you send me the full request made to hubspot, and hubspot's error that you received? Thanks