What is the ruling on one who masturbated during the daytime in Ramadan, knowing the ruling, and does not know the number of days he did that?

If a fasting person masturbates and semen is ejaculated, their fast is broken. If no semen is ejaculated, then their fast is valid. Masturbation is a forbidden act and it breaks the fast if done intentionally and semen is ejaculated. The person must make up the days they broke, repenting to Allah. Masturbation is forbidden in Ramadan and at other times.