MAC address is different to the BSSID address. Is this normal?

I'm doing a project for a cybersecurity course in college. My task is basically to brute force my way into my professor's router.

In the instructions, the professor gave us the MAC address of the router, which is "XX:XX:XX:XX:XX:4F". I ran "airodump-ng wlan0mon --wps' to find the channel of the network and found that the BSSID was being reported as ""XX:XX:XX:XX:XX:51" (the Xs are the same digit to that of the MAC address).

I tried to establish the 4-way handshake between my environment and the SSID/router using the provided MAC address and the hadnshake was never established. It did work with the BBSID.

From what I researched, BSSID and MAC address are the same thing. Am I missing something at play here, or the information that I got was wrong?