What is the explanation of the my two Hadiths: "Whoever does not pray Witr is not one of us," and "Indeed, Allah has added a prayer for you, which is Witr"?

First: The hadith "He who does not pray Witr is not of us" has a weak chain of narration. The meaning of "not of us" is "not following our Sunnah and way." The authentic hadiths indicate that Witr is a confirmed Sunnah and not obligatory. The word "right" (in other contexts, e.g., "Witr is a right") means an affirmation of its Sunnah status and an urging not to be negligent about it. Scholars have unanimously agreed that Witr is not an obligatory prayer.

Second: The hadith "Indeed, Allah has added a prayer for you, which is Witr, so pray it between the 'Isha prayer and the Fajr prayer" has a sound chain of narration. The meaning of "has added for you" is "has given you and provided you." It does not contain evidence for the obligation of the Witr prayer; rather, it is a clarification of Allah's favor upon His servants and an evidence for the Sunnah status of Witr, not its obligation. Among the proofs for this is that the Prophet (peace be upon him) prayed Witr with different numbers of rak'ahs (three, five, seven), and he prayed Witr while on his riding animal, which is not permissible for obligatory prayers.