@raghu maremanda​ ,

you didn't add the .mode() in your code shown.

it's still:

d.write.format("delta").saveAsTable("delta.devices_new")

I am not sure if this will help, but try:

d.write.format("delta").mode("append").saveAsTable("devices_new")

also, the error doesn't tell much. can you share the error thrown?

thanks,

Pat.