Is the hadith: "Preserve your semen" authentic or not?

The aforementioned wording was not reported. However, An-Nasa'i narrated from Shakl bin Humayd, from his father, who said: "O Messenger of Allah, teach me a supplication by which I may benefit." He (the Prophet) said: "Say: 'O Allah, protect me from the evil of my hearing, my sight, my tongue, my heart, and the evil of my maniyy.'" The term "maniyy" was interpreted as referring to the male organ, or seminal fluid, or fornication and immorality. Al-Albani graded it as sahih (definition) (authentic).