What is the ruling on calling a person by a shortened nickname derived from their original name, such as "Sateef" for "Mustafa" or "Razzooq" for "Abdul Razzaq"?

There is no harm in changing a name or adding letters to it, as long as it does not involve diminishment or mockery. Imam Al-Bukhari titled a chapter "Whoever called his companion by shortening his name by a letter." Shortening or adding is not forbidden unless it becomes a matter of calling by offensive nicknames or disparaging, as Allah Almighty says: "And do not call each other by [offensive] nicknames. Wretched is the name of disobedience after [one's] faith." An exception is made if the change involves an assault on the name of Allah or the Prophet.