@Fahmihamzah84 This appears to be an issue with your schema.  The BigQuery error is suggesting an issue trying to cast a string into a collection (array/list/ect).   It's hard to tell which array may be causing the issue as there are many.   My suggestion is to set the processor to log level DEBUG and see if you can get more verbose error.   This will help you figure out which field or fields is the culprit.      Keep in mind it could be one of the empty arrays too.     I do not suggest the following as a solution just as path to figuring out where the problem is.  Sometimes when i have issues with type casting,  i make everything a string temporarily and for development.  If you do this carefully one at a time, when the error goes away, you can determine which field it is.   This also helps you identify a working state for your flow and allow you to work from that operational base to find solution for the end schema being the format you need. ... View more