Interactive Brokers Platform/ Probability of profit

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Hi there, I am new to using the IB/ TWS platform. My understanding is that the probability of ITM can't be displayed in the option chain in TWS. As a substitute you can use the option's delta, however that does not seem to correlate very well. I would expect deviations in the low one digits but get much bigger differences. For example, in the attached screenshot I am looking at selling a 70.7 delta put on the SPY which should have a probability ITM of around 30% (1-70.7%) , then looking at the quote details shows me a probability of profit 59% which is quite far off? My only explanation would be commisions but is that it? Really stuck here so help is really appreciated? Many thanks!