Randomly Not Post order

Why sambapos 5.7.16 randomly not saved second order to db?
Problem similar when 2 computer open the same table, and order not saved.
But now it happens just 1 computer open table and randomly not saved order to database.
Before at sambapos 5.7.14 not happens.
Now I scare to update to sambapos 5.7.18

When you say it is not saving the order, are you getting a popup saying the ticket has not been saved? If so, that will be because someone has opened the same ticket on another terminal, made changed then closed the ticket whilst the ticket has been open on the 2nd terminal. In this case, because changes have been made on that ticket during the time it was open, you cannot save your changes because the ticket has changed since you first opened it.

Make sure you don’t have the same ticket being worked on at the same time from different terminals.

Also, if it is how I described here, this would not be new to v5.7.16 - it has been like this for a long time.

Johan,
Today we will release a new version. We fixed that problem in 5.7.20