Trying to amend my 2023 taxes by adding a 1099-B. When I go to manually add it, TurboTax's web page glitches with an error page. Clearing cache, cookies, does not work.

We've also been in touch with Customer Service & they have no idea why this is happening. Nothing on our end is leading to this (we're running the latest Mac iOS, have cleared browsing data, etc.).