[ULR] ALWAYS returns internal error, code 409

Please help. This used to work (last used about 6 months ago) but now I get "Internal Error" Code 409 when trying to check the status of a batch copy.

https://api.dropboxapi.com/2/files/copy_batch_v2 returns:

{

  ".tag": "async_job_id",

  "async_job_id": "dbjid:AACfK9NJvJ3Z6Axo9sOaJozr8D3Gv4x6BuGKZm9dupHKHJQ-UGBYldByYfxglFQJ1rrmHOg3gSpWysydPpNsCoc9"

}

.

.

jobId = results["async_job_id"]
load = {
"async_job_id": jobId
}

https://api.dropboxapi.com/2/files/copy_batch/check_v2 using the job id obtained above returns:

{"error_summary": "internal_error/..", "error": {".tag": "internal_error"}} )

which is very unhelpful.

Please advise

Tim