It's unusual that you're receiving calls from a contact named "Max Audio" with no visible phone number. If you have "Silence Unknown Callers" turned on, it should ideally block calls from unknown numbers.
Unfortunately, iPhones don't currently offer the ability to block calls based solely on the caller ID name. Blocking relies on phone numbers, and even though "Max Audio" isn't showing a number, the system still registers a unique identifier for that specific caller
To improve understanding of the phenomenon, it would be highly beneficial if you could share a screenshot. Visual representations carry greater impact than written descriptions.
Please remember that this is a public forum, so when attaching a screenshot, please avoid including any personal credentials such as IP addresses, card details, email IDs, Apple IDs, IMEI numbers, serial numbers, phone numbers, order IDs, or any identifiable location information if you are sharing a map.

With the limited information that you have provided, It is hard to even guess the problems faced by you.