Hi Xu,
I am also getting today the same error as discussed before by Yuri, Matthew, Pavel & Johannes.
The error message reads as follows:
Unable to create trial instance 'debashish': Internal Server Error (500) - Unexpected exception in createSchema() called with account 'p1941098499trial', schema 'debashish', DB Type 'hanaxs', DB Version '1.00.74.00.390550', and DB Server 'null'
Please do the needful and get same fixed.
Regards--
Debashish