Why parted error

[yzn严哲南]

I have a big usb3.0 storage disk

I input a command: mklabel gpt

But return an error message:

Error Partition(s) 16  have been written, but we have been unable to

inform the kernel of the change, probably because it/they are in use.  As a

result, the old partition(s) will remain in use.  You should reboot now before

making further changes.

How to solve the problem?

I am eager to get the answer.

I am very grateful if you solve it.