Has a recent update made ChatGPT really stupid?

Indeed, 2 days ago, ChatGPT very often gave me really very relevant answers and since yesterday, it has been incomprehensible, the answers it gives me are off the mark. Regularly each of the answers he offered me worked very well, but since yesterday, I can clearly see that he has changed, his answers are no longer as relevant and I have to torture my mind to succeed in obtaining satisfactory answers. Have people noticed a sudden change in the effectiveness and relevance of ChatGPT responses?