everyone.

I have a question regarding surah ikhlas. Someone was telling me today that for the salat that includes 3 or 4 rakats, your not supposed to read Surah Ikhlas? I know this isn't true but I dont get it. I don't know why this person said that. Thing is this "person" has been tellin my cousin this. She recently started praying and she wanted to know. Obviously this doesnt sound right. Sooo if it's not, can you guys explain it to me with evidence, so i can show it to her InshaAllah. It's pretty important obviously. Or does anyone know a good site where I can ask? InshaAllah. Ok my mom doesnt know I still come on this forum lol. So InshaAllah a reply from a reliable scholar would be better otherwise, at least some evidence