When will the issue with stimulus checks be resolved and why is this a problem now but not with the 1st stimulus?

[CatinaT1]

We are happy to share that stimulus payments will begin to be deposited on January 8th for millions of our customers affected by the IRS error. We expect most of these payments to be available that day, but banks could take a few business days to process.

Payment will be deposited into the same bank account that customers received their 2019 tax refund.

Customers receiving a stimulus payment will receive an email from TurboTax letting them know their stimulus payment is on the way. We have been working tirelessly with the Treasury and IRS to get stimulus payments to our customers. We know how important these funds are for so many Americans and we regret that an IRS error caused a delay.

Please note the following page for additional information: Why Haven’t I Received My Second Stimulus Check? 

[Opus 17]

This announcement by SBTPG bank has a pretty good summary of what went wrong. https://www.sbtpg.com/coronavirus-stimulus-payment-info/

Basically, it was a big problem the first time too, and the banks were allowed to break the rules to fix it.  Then the IRS said for round 2, "don't break the rules just send the money back like the rules say," and then the IRS screwed up even worse in round 2, so after 3 days of dithering the IRS says to the banks, "it's ok to break the rules and fix our mistake again."