Interesting but...

I will say a lot of the levels are super challenging, some to the point of nearly impossible, but fun and clever. Its been fine up til a few days ago when I was playing level 7 on the annex elevator, after not quite understanding the solution at 2am, I exited out of the app to look up some help to figure out what I wasnt understanding. After going back, the annex levels no longer work, every time I tap on it it does nothing and I end up in the previous "location" I was playing (any other level but the annex levels) before trying to switch to the annex levels. It would be great if this bug could be fixed so I can continue with the annex levels.

saya III about 100 Floors - Can You Escape?, v3.9