TEAC DVW-D11 CD/DVD duplicator

[Cian]

Sorry if I am a bit off the forum. I don't know what forum would be best to post it. I suppose all of you, music
aficionados, duplicate your music CDs so I hope you might have some helpful ideas. Here is the problem. I have
TEAC DVW-D11 CD/DVD duplicator that caused some problems today that I can not figure out. I duplicated/copied
one CD multiple times yesterday with no problem. However, I tried duplicating two more CDs today and the duplicator
just shows "copying" on the screen but no actual copying happens. All three CDs are my music, recorded on
Boss BR-1200. I finalized all three CDs after recording and I can play them on any CD player with no problem.
I use Tayio Yuden medium. I am completely flabbergasted and can not find out what's going on. By the way,
I used 3 or 4 different CDs in the case something was wrong with discs but to no avail. Do you have any idea
what could possibly go wrong?
Thank you so much.