If you try to connect an external device to your MacBook Pro (13-inch, 2019, Two Thunderbolt 3 ports) and it's not recognized, the device might be trying to use too much power from your Mac and may not be compliant with Thunderbolt 3 (USB-C) power specifications. Mac computers connect to external devices, like external hard drives, that are compliant with the USB specification supported by Thunderbolt 3 (USB-C).
Try using a USB hub, Thunderbolt 3 (USB-C) hub, or power adapter
If your external device needs more power than your Mac can provide, try connecting your device to a powered USB or Thunderbolt 3 (USB-C) hub, or try connecting your external device to its power adapter. Then, connect your hub or external device to your Mac.