Try to change another USB interface for this hard drive and see whether it can be read on your computer.
If it can be read there, you’d better copy out all your stored data quickly or use some data recovery tools to help you, like:
icare-recovery.com/seagate-recovery/seagate-external-cannot-be-recognized.html
But, if it also cannot be read well there, for the data, some data recovery companies may help you out. But, as to the drive, you’d better replace it for future use.