Is it obligatory to repeat the prayers that were performed after the emission of a sticky fluid which I thought was semen, then it became clear that it was madhy (prostatic fluid), knowing that this situation continued for two years? And what is the ruling on this in the Shafi'i school of thought?

Pre-seminal fluid (madhy) does not necessitate a full body ritual bath (ghusl); rather, it only requires washing the male organ and performing ablution (wudu'). If a person who is in a state of minor ritual impurity performs ghusl with the intention of removing the impurity, or usually with the intention of removing major impurity (janabah), and arranges the ablutionary limbs in order during the ghusl, then it suffices for wudu'. However, if the limbs are not arranged in order, it does not suffice, and he must repeat the prayers he performed with that ghusl, unless he performs wudu' after the ghusl, in which case there is no issue.