I had two returns in 2019 and 1 of my 2020 no send and this last one cost me thousands in penalty because i owed. One sent but somehow the second did not. And i know i hit the send button. Not impressed. Went to H&R Block. It turns out its cheaper by far than the cost of the mistakes. I will never do my own taxes again. And the penalty for being late by almost a year was huge. A very dissatisfied ex-customer.