Barracks not trainning troops

[ThisisI]

I am trainning troops and since it was taking too long, I started to upgrade the Barracks to lvl 4 and put the new Drill Serg Skunk onto.
I came back later to use the troops several hours later and have noticed that they havn't been trained. I noticed then that the timer has been stuck. Is this a bug or do troops not get trained when the barracks are being upgraded?

[Sammuel]

Troops won't train while barracks is upgrading.

[ThisisI]

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