Why are some of the buttons not working on my calculator?

This sounds a lot like a hardware problem with a circuit that’s broken for that key column. Unfortunately, I don’t know how to help you fix the issue from the hardware side and from the information I gathered I don’t think you’ll be able to fix any hardware issues before your ACT. However, MateoConLechuga may have away to fix it through software

• Press [prgm] (If that button doesn’t work leave a reply and I’ll describe how to do it another way)
• Scroll to the right over to ‘NEW’ and press [enter]
• Type in the letter A and press [enter] again
• Press [2nd]>[0] and scroll down to Asm84CEPrgm (If this is crossed out in blue, leave a reply and I’ll describe how to do it another way)
• Press [enter]
• Now type in EXACTLY the following characters (they should be on the same line as the Asm84CEPrgm token)
• 210100F53678C9
• Press [2nd]>[mode]
• Press [2nd]>[0] and scroll down to Asm( and press [enter]
• Press [prgm]
• Press [enter] on program A
• Your screen should look like Asm(prgmA
• Press [enter]
• If it just says ‘Done’ then it should have worked. Try the buttons again and let me know if they work again!

Since your calculator may not be reliable, I think your best bet is to see if your ACT proctor has a spare calculator or if some student brought along a spare. If there’s no spares, then just know that most commands and operations you need are available in the catalogue (which you access by pressing [2nd]>[0]).