Help!! First time Options trade, finished in money - Now my account is in margin call

So I got tilted and bought 750 options contracts for 1 cent that somehow ended up in the money the last minute. Now I'm in a margin call for 24k but my cash and cash alternatives is showing 260k.

They won't let me sell any of the 75k shares that are showing up in my account to cover the margin call. I'm guessing I need to deposit the 24k to get access to the 75k shares? How long do I have to exercise buying all the 75k share? I want it but need to find 24k to deposit. I think I'm evaluating this correctly. Please let me know how these options stuff work.

Thanks