There are some limits that you can be hitting:

• Row Size for Delta Sync Index: The maximum row size is 100KB.
• Embedding Source Column Size for Delta Sync Index: The maximum size is 32764 bytes.
• Bulk Upsert Request Size Limit for Direct Vector Index: The maximum size is 10MB.
• Bulk Delete Request Size Limit for Direct Vector Index: This limit is not specified in the provided context.