Cloude Sonnet 4 works as 3.5

Over the last two days, I have observed a significant degradation in Cloud Sonnet 4. Today, I checked the model, and it replied that it is version 3.5. Model 4 thinking identifies itself as 4. Two days ago, the results were fantastic, but today, its output is terrible! I added a screenshot of how the model identifies itself.

I checked all the models, and they identify themselves correctly but only sonnet 4 shows it 3.5.

This has been debunked as false response by Claude so many times in the forum.

Anthropic does not give the models an number, they are just called ‘Claude’.

Since Claude 3.5 Sonnet was in the training information of Claude 4 it is known and sometimes Claude 4 hallucinates the name.

Danke schön