I was praying isha snd during the prayer,my scarf slipped down a bit in front of my eyes. I was still kind of able to see so I just continued praying but I don’t know if it invalidates my salat in any way if my eyes are covered. Does anyone know?
The only thing that may invalidate your prayer in the context of clothing is if you disclosed your 'awrah it means in case of hijab if for example your hair (a part of it) was visible, or your neck or cleavage depending on what it usually covers.
As a matter of fact if a part of the 'awrah is shown there's a difference of opinion among scholars whether the prayer is valid or not. And also depending on whether you know it or not or you did it intentionally or not. And how long it to took the person to cover it again if he/she came to know that it was disclosed.
In the Maws'oa al-Fiqhiyyah -see here in Arabic- you may read:
In the following I'll translate from Aarbic language, as these translations are of my own take them carefully.
120 - ستر العورة شرط من شروط صحّة الصّلاة كما تقدّم، فلا تصحّ الصّلاة إلاّ بسترها، وقد اتّفق الفقهاء على بطلان صلاة من كشف عورته فيها قصداً، واختلفوا فيما لو انكشفت بلا قصد متى تبطل صلاته؟
Covering the private parts ('awrah) is one of the conditions for the validity of the prayer, as stated earlier, so the prayer is not valid unless it is covered. The fiqh scholars have agreed on the invalidity of the prayer of one who intentionally uncovered his private parts in it, and they differed on the cases in which the prayer would be invalidated if it was unintentionally exposed.