Just like @mervyn said, I don't think IB allows you to buy options when it sees you won't be able to fulfill any auto-exercise/obligations that can happen upon expiration. With these calls, if you have them on auto-exercise, you will be on the hook to buy all the shares from these calls which is more than the funds that you have in your account even with margin.
At least you'd get some cardio walking down to the corner store that sells the tickets. And I hear half your losses get donated to the public childcare system. I knew this guy who used to call them "suicide options"... I assume because you'd only buy them if you had nothing to live for; lol. He'd brag that he liked playing them but they're not my cup of tea. Last time I saw him he was scrounging through his couch cushions for extra money so that he could ride his bicycle to go get cigarettes. IDK if there's a cause and effect there though... good guy anyway. Fun at parties
Usually any warning text with a yellow background can be overridden manually. But any error message with a red background will stop a trade from being accepted by IB.
I don’t know, simply check the account overnight buying power. If it is within limits, you can trade. OP can try, for example, a 2.5k call options at 2 cents expiring next Friday, that it is way out of money, maybe the broker can take the trade. I did large volume calls 6-9 months out on AAPL, TSLA, AMZN, etc, all work out.
I guess a broker bug related to margin acct. With a cash acct it should go thru, IMO, b/c then only checked for availability of $5000 (=2500 * 100 * 0.02) + commission.