What is the ruling on someone who feels a slight release of gas during prayer, which prompts him to repeat ablution and prayer many times, and he is unable to apply the Prophet’s (peace and blessings be upon him) saying: “He should not leave (the prayer) unless he hears a sound or perceives a smell”?

Your problem is the waswasa (whispering of Satan) through which Satan tries to corrupt your worship. Its cure lies in casting off these whispers and not paying attention to them. Perform ablution and pray without hesitation, and if Satan whispers to you that something has exited, do not respond to him. Even if we assume there was an involuntary release of wind, the matter is simple: it suffices for you to perform ablution after the time for prayer has begun and pray with that ablution until the time for prayer ends, and whatever exits after that will not harm you.