[solo]

If you are sure that none of the 3 items appeared on turn X+2, this suggests there is a bug. If one or two did show up, then a bug is less likely. Too bad you never got a chance to look at Turn X+1, before it was hosted. Seeing X+1 might have also confirmed that X itself was not stalled, too.

If there is a bug, I might have experienced it myself one time in a game where none of my moves were stalled.

Turn X: I forge an item
Turn X+1: It does not show up, so I forge it again, believing I goofed up my orders on Turn X.
Turn X+2: Two copies of the item appear in my lab!

The lab was nearly empty, so I doubt I would have missed seeing the item on Turn X+1, but who can say for sure!

If no bug exists, then the cause might be:

1) Full lab
2) Equipment change made to a forger after the forge order was given. This can cancel the forge order without you realizing what happened, especially when gems are in short supply and/or the magic item is a booster or a forging hammer.
3) Lack of gems and you did not notice there were not enough to forge the item you wanted.
4) Desired item is so dark it blends in with the dark backgrounds used in the lab display, and you just did not notice that it was there.
5) You somehow cancelled a forge order without realizing what happened. However, this happens more often with move orders, especially just before a moving elsewhere to deal with another province.
6) Exiting the game and then coming back later to continue working on your turn may produce unexpected changes to unit orders, but this would be another kind of bug.