Wa `alaykum as-Salamu wa Rahmatullahi wa Barakatuh.

 

If you wiped the madhy clean, then your prayer is valid as long as you have performed wudhu before prayer.

 

Ideally, you should wash your private parts in case of emission of madhy before performing ablutions for prayer.

 

If you forgot to wash your genitals, then you are excused as long as you have wiped it dry by using tissues, etc. The Prophet (peace be upon him) said, “Allah has forgiven my ummah of their unintentional mistakes or forgetfulness…”

 

Allah Almighty knows best.