Delta Live Tables (DLT) can indeed process multiple streaming tables within a single pipeline.

Here are a few things to check:

1) Verify that each streaming table has a unique checkpoint location. Checkpointing is crucial for maintaining the state of streaming queries, and conflicts can arise if the same location is used for multiple streams.

2) Ensure that first_schema and second_schema are defined correctly and match the structure of the JSON data in first_source_path and second_source_path, respectively.