Telegram Account Recovery Blocked by Inaccessible Old Phone Number

I can no longer access my Telegram account on my Android phone (Redmi Note). My account is linked to an old phone number that I have completely lost access to, so I cannot receive the login codes that are sent via SMS or call. I have a backup email address registered with my Telegram account, but the system does not allow me to log in or receive a verification code using this email. I also have two‑step verification activated and I still remember my password correctly. However, I cannot get past the login stage, because the activation and verification codes are only sent to the old phone number. I am therefore locked out of my own account. I contacted Telegram support regarding this issue but I have not received any response so far. I have been unable to use my account since September 9, 2025, and this situation is causing me serious inconvenience. My expectation from Telegram is to enable the use of my registered backup email address as a secure method to receive the login code and verify my identity, or to offer an alternative identity verification method so that I can safely regain access to my account without needing the old phone number.