The same issue. I have an iPad Air 5 (2022) cellular 64Gb running iPadOS 16.3, Telegram client is updated to the latest version. When someone calls and I’m answering using another client on Windows or Android, my iPad client hangs on calling until I answer (nothing happens) or cancel a call. I can collect logs or any other information if needed
Please note: Tlgr.org is an unofficial version (hereinafter the 'mirror') of the site Telegram.org. This mirror was created to be able to access the official website Telegram.org at any time while it is unavailable due to any local network problems. If the official website Telegram.org is available, we recommend using only that. The transmitted information is not stored on the mirror side and is provided on an as-is basis.