I don't know what is this problem called, but please someone, help me.

Click the Mount button, shown below:

The error "com.apple.DiskManagement.disenter error - 119930874" typically indicates that there is an issue with the disk partition or file system on the external drive. Here are a few steps you can try to resolve the issue:

1. Restart your MacBook and reconnect the external drive: Sometimes, simply restarting your MacBook and reconnecting the external drive can resolve the issue.

2. Try connecting the drive to another port: If the external drive is not being recognized, try connecting it to another USB or Thunderbolt port on your MacBook.

3. Use Disk Utility to repair the drive: Open Disk Utility, which is located in the Utilities folder of your Applications folder. Select the external drive from the left-hand menu, and then click on the "First Aid" button. This will scan and repair any errors on the drive.

4. Use Terminal to repair the drive: If the Disk Utility is unable to repair the drive, you can try using Terminal to repair it. Open Terminal, which is also located in the Utilities folder of your Applications folder. Type in "diskutil list" to identify the disk identifier for your external drive. Then type in "diskutil verifyDisk [disk identifier]" to check for errors. If errors are found, type in "diskutil repairDisk [disk identifier]" to repair them.

5. Format the drive: If none of the above steps work, you may need to format the drive. Note that formatting the drive will erase all data on it, so be sure to back up any important files before proceeding. In Disk Utility, select the external drive from the left-hand menu, and then click on the "Erase" button. Choose a format that is compatible with your system (e.g. Mac OS Extended) and give the drive a name. Click on "Erase" to format the drive.

If none of these steps work, the external drive may be physically damaged and will need to be replaced.

Most likely, that disk has failed. You may be able to "repair" it by selecting the following: