Those drives have been problematic for many posting here.
The likely problem is a lack of power to the drive. Low-cost drives like that have to get all their power from the computer's USB port. As the drive ages, its motor can demand more power. If that exceeds what the port can supply, the drive does not work properly.
Some workabouts that don't involve binning the drive:
1) The drive is probably formatted for Windows. Sometimes using Disk Utility to erase and reconfigure the drive as GUID Partition Table and Mac Extended (HFS+) wil make the drive work better. However, this means;
a) that you need a way to offload the existing files on the Passport while reformatting, and
b) that you do not need to share the drive with a Windows computer.
Ref: Erase and reformat a storage device in Disk Utility on Mac - Apple Support
2) Get a POWERED USB hub. It will come with an independent power supply that take care of the Passport's power demands. Place the hub between the Passport and the computer. A hub lacking an external power supply will only make the problem worse.
3) If you have two empty USB1 or USB2 ports, get a "Y" USB cable. It gets power from two computer ports to give the drive more power. The downside is a lack of empty ports or a newer Mac with only USB-C ports. Reference here.
The best of all worlds solution is to bin the existing drive and get a better-quality model. After years of struggle with the "name-brand" drives that go on sale every other weekend. I now use only Mercury Elite Pro and Mercury Elite Pro Mini enclosures from Other World Computing. Zero issues since the switch. References here and here
