Error while reading data

[Ken1010]

Hi, 

I'm trying to create an external table linked to a bucket, the initial load works fine but as the files in the bucket grows, I get the following error. There are files that drop into the bucket every 30 mins.

Error while reading data, error message: Too many values in line. Found 18 column(s) when expecting 1.; line_number: 1 byte_offset_to_start_of_line: 0

I'm relatively new to the GCP, so I not sure where and how to resolve this issue, any help would be appreciated.