Summarization call on image sometimes returns empty string today after working for weeks

Has there been some change to how images are supposed to be processed for summarization?

I have an image that I’ve been using for over a month (processing repeatedly to test smth else), and yesterday the 4o model summarization output is sometimes empty (not consistent).

Seeing the other threads on this, it’s disappointing and confusing that openAI seems to force its users to use other providers.