Unknow Error - Substituting players

[Cods3003]

I am running tourneys for with an include list and I normally have a couple of players that volunteer to be a sub for the tourney.

I use substitute-select option via the right click on the player within Show Tables.

Most of the time it works but recently I just get a message saying unknown error. Yesterday I was able to sub player A and then reseat the original player with they returned. Then when I tried to use Player A for another drop-out I just kept getting the same unknown error message. Sometimes using substitute - any works and then I can replace that sub with Player A but not always

 

Can anyone tell me if any of the below are possible causes:

1. Player A was kibitzing on one of the tourney tables when I asked them to sub

2. Player A restricted to subbing only once - I assume this might have something to do with scoring

3. I am doing something wrong - if so any ideas what it might be.

 

Thanks for any assistance

[Gerardo]

A sub can be used only once per tourney.