I CAN'T BUILD "SIMTOWN EXPRESS"

I can't build simtown express because "stable is already under construction". I don't have any discovery mission, task, event, or other build. But I still can't build the simtown express. That's make me frustrated. I stuck in level 13 for a long time, and online support didn't help me. They told me that I should have 250.000+ simoleons, I did it, but still cannot build it. I changed my device, but still not working.

How to fix it? (I dropped the pic of this problem)