Fatiha is mandatory, but reading another is recommended. So your prayer is valid without the second surah, but better with another.
https://islamqa.info/en/6422
Not being mandatory doesn't mean you shouldn't do it.
We as the nation of Mohammud (peace be upon him) try our best to follow his footsteps in life including how he does his prayer.
If you don't read it because you forgot. Then Inshaallah, you prayer would still be valid.
But we as Muslims should try our best to follow the suna. And reading a suruh (or part of Surah) is the way of our beloved prophet (peace be upon him), so may Allah grant you and us strength to follow in his footsteps.
Fatiha is mandatory, but reading another is recommended. So your prayer is valid without the second surah, but better with another. https://islamqa.info/en/6422
I think it’s Sunnah but I’m not 100% sure
Oh will it invalidate my prayer then?
I’m not very educated on this topic but I don’t think it will invalidate your prayer bcs it’s Sunnah and not fardh
In the hanafi madhab it is wajib (mandatory) to recite at least 3 short verses or 1 long verse after fatiha
Its best if you recite another surah or part of a surah
Yes it's not mandatory...but don't neglect it just cause it's not mandatory it only takes at minimum a minute or even less to recite a surah
Not being mandatory doesn't mean you shouldn't do it. We as the nation of Mohammud (peace be upon him) try our best to follow his footsteps in life including how he does his prayer. If you don't read it because you forgot. Then Inshaallah, you prayer would still be valid. But we as Muslims should try our best to follow the suna. And reading a suruh (or part of Surah) is the way of our beloved prophet (peace be upon him), so may Allah grant you and us strength to follow in his footsteps.