What is the ruling concerning the prayers performed by one who suffers from urinary incontinence, and who cleans himself, takes precautions, yet urine is discharged from him before or during ablution, or in the interval between the place of cleaning and ablution? And does what is discharged of urine after cleaning not harm the incontinent person? Or after ablution?

If the incontinence is continuous most of the time, then after performing istinja (washing after relieving oneself), you should wear a diaper to prevent the spread of urine. You are not required to repeat istinja. You should perform wudu for each prayer after its time has begun, and pray the fard (obligatory) prayer and any supererogatory (nafl) prayers you wish.

If the incontinence stops at a specific time, then you should wait for that time to perform wudu and pray. Some scholars hold the view that a person suffering from incontinence is not required to perform wudu for every prayer, nor to wash the impure area.

Your previous prayers are valid, Allah willing.