I play on Xbox one X enhanced from a purchased disk. Recently, in Miami, the prompt to pick up the letter, that is with the car bomb in the safe, won’t appear. So, you can’t make the phone call to Robert Knox for the explosive liaisons challenge.
It does seem to be a bug that happens to Xbox players, and probably not only in the Miami level. Unfortunately, HITMAN 2 will no longer receive any fix from IOI. So the only thing you can probably try is to restart the level over and over til the prompt appears.
The November Update is the final planned patch for the game and to make sure that the game is in a good place for the future, we’ve kept the number and magnitude of fixes low, which will enable us to continue ramping up our work for the next Hitman game.
(quoted from https://www.ioi.dk/hitman-2-november-update)
If you search the forum there are a few comments about this problem, I had an exchange with someone about exaxtly this. I did a couple of videos which might or might not still be there (not in front of the thing right now). I think if you find an xbox dvr site and look up my gamertag (same as name on this forum) you’ll see two or three videos of this where I spent some time trying different approaches to getting the bomb. Sometimes it works, sometimes it doesn’t. I didn’t find anything systematic but believe it’s related to how items spawn in the level, I think they spawn in the air and drop down but it’s a little random and if [something] happens during this process then one phases through the bottom of the safe and can’t be picked up.