If re-attaching the cable at the drive and computer does not solve the problem it may be a hardware fault from dropping the drive. I believe this drive has a removable section on the end where the cable attaches. Make sure that has not loosened when the drive fell, You can see the removable adapter here.
If reattaching the cable does not work then try the following.
Here is a video showing how to remove the bare drive from the enclosure. Avoid touching the Printed Circuit Board of the drive. Dropping the drive may have affected the USB bridge card but left the drive unaffected. If you remove the drive and attach it to another computer either internally or by using another enclosure, you can see if the drive will be detected. If it still is not detected, then the only way to recover the data would be from a Professional Data Recovery Service.