Vouchers in General Ledger

Hello guys,

Hope all is good for you,

When we open a General Ledger the system assigned us a voucher, but seems like the same voucher can be assigned to another user working in the same module.

See the error below:

We don´t understand the reason of this, because a voucher taking by me couldn´t be available for another user in our knowledge.

Which is the logic on this?,

Hope you can making lights to us

Thanks a lot,

Emely