Does masturbating out of forgetfulness during a daytime fast, other than in Ramadan, invalidate the fast?

Masturbation is forbidden for both the fasting and the non-fasting person. Your fast is valid because the masturbation occurred out of forgetfulness, and error and forgetfulness have been lifted from the Ummah. Whoever breaks their fast out of forgetfulness is not required to make up the day or offer expiation. And whoever masturbates out of forgetfulness does not invalidate their fast, whether it is an obligatory or a supererogatory fast.