Is the emission of semen (manyi) or pre-seminal fluid (madhi), if its ruling is unknown, considered a sin that necessitates repeating the prayer?

We fear that what you mention might be a deception from Satan and a whisper (waswasa), for these discharges might be natural and have no connection to madhy (pre-seminal fluid) or mani (seminal fluid), unless accompanied by clear indications that they are either of them, such as thinking (about sexual matters) and arousal of desire, and you find in them the characteristic signs of either madhy or mani. In the event that it becomes clear that what was discharged from you is mani or madhy, you must purify yourself before prayer, and repeat the prayer if you prayed without purification.