An "AttributeError: 'NoneType' object has no attribute 'shape'" when building phylogenetic tree using Augur

By the way, I did a “test” run using a 49 sequnences fasta file to see if it’s applicable. I did get the treetime file I want in that 49 test. Yet this time I confront with this error with my larger 1500 sequences fasta.I hope this information could be useful.