Two Questions on Baptism

[The27thPsalm]

1. If a Catechumen is baptized and has held on to heretical beliefs during their baptism, do they need to be baptized again even if they later fully repent of their wrong belief?
2. When the water is poured on a person’s head, does it need to touch the scalp or some skin to be valid?

[angell1]

to both questions, not that I am aware of

[Horton]

If a Catechumen is baptized and has held on to heretical beliefs during their baptism, do they need to be baptized again even if they later fully repent of their wrong belief?

No, once validly baptized there is never a need to be another.

When the water is poured on a person’s head, does it need to touch the scalp or some skin to be valid?

The priest who does the baptism knows what is required for a valid baptism, trust he got it right.

[The27thPsalm]

Thank you @angell1 and @Horton for your replies.