Ruling on one who has intercourse with his wife during the day in Ramadaan a number of times, not knowing the ruling

Undoubtedly
Allaah has forbidden His slaves to eat, drink or have intercourse during the
day in Ramadaan, or to do anything that might break the fast.  He has
enjoined that the one who has intercourse during the day in Ramadaan, who is
accountable, of good health and settled, not sick or traveling, has to offer
expiation (kafaarah), which is freeing a slave; if he cannot afford that,
then he must fast two consecutive months. If he is unable to do that then he
must feed sixty poor persons, giving each one half a saa’ of the staple food
of the country. But with regard to one who has intercourse during the day in
Ramadaan, and who is one of those who are obliged to fast because he is an
adult, in good health and settled (not traveling), but he was ignorant of
the ruling – there is a difference of opinion among the scholars in this
case. Some of them said that he has to offer the expiation because he was
negligent and did not bother to ask and find out about the religion. Other
scholars said that he does not have to offer expiation because of ignorance.
From this you can know that in order to be on the safe side, you should
offer the expiation, because of your negligence and not asking about what is
forbidden for you before you did what you did.  If you cannot free a slave
or fast, it is sufficient for you to feed sixty poor persons for each day
that you had intercourse. So if you had intercourse on two days, you have to
offer two expiations; if you had intercourse on three days, you have to
offer three expiations, and so on, one expiation for each day you had
intercourse. But if you had intercourse several times on one day, one
expiation is enough for that. This is so as to be on the safe side and this
is better for you, so that you will be free of blame and will avoid an area
concerning which there is scholarly dispute, and to make up for your fasts.
If you do not remember the number of days on which you had intercourse, then
do what is on the safe side, which is the higher number – so if you are not
sure whether it was three or four days, assume it was four, and so on. But
you should not do anything except what you are sure about. May Allaah help
us and you to do that which pleases Him, and frees us from blame.