Samsung SSD stopped being recognized

Try restarting your computer.

Try an SMC reset and a PRAM reset (hold the PRAM reset for a full minute so it activates several times).

Are you using the Samsung software to access and manage the drives? If so, see if they have an updated version of the software and driver. While utilizing the built-in hardware encryption of the SSD is nice, it does leave you vulnerable if a macOS update breaks the third party software/driver. Many advanced users here will tell you to just use Disk Utility to manage the SSD and use Filevault if you want the data encrypted.

Boot on Bootcamp do the password,( windows wouldn't see Samsung T3). restart. catalina sees T3 formated to mac os journaled.