Uninstall Bitdefender completely using their (not Windows Add/Remove). Then sign up for a new trial with a different email. Works once or twice before hardware block.

Bitdefender Total Security is an excellent, lightweight, and highly effective security suite—it is genuinely worth paying for. If you cannot afford it right now, use the official free version or an alternative reputable free antivirus like Avast or Windows Defender until you can snag a legitimate, discounted license.