asset-timeseries mapping issue

I have a dataset which consists of Assets.
and another dataset which consists of timeseries.

I wanted to map assets to timeseries 
But ,i am getting access issues.
FYI.
We have been given all required access (i.e. read and write).

 

Query:

WITH assets AS (
    SELECT  id,name
    FROM _cdf.assets
    where dataSetId = dataset_id("test_assets")
),
tagname AS (
  select tagname as tagname,
  name as assetName
  FROM `test_assets`.assets
),
time_series AS (
    SELECT name, externalId 
    FROM _cdf.timeseries 
  where dataSetId = dataset_id("test_timeseries")
)
SELECT  ts.name, a.id AS assetId
FROM tagname t 
INNER JOIN assets a ON a.name=t.assetName
INNER JOIN time_series ts ON ARRAY_CONTAINS(t.tagname, (REPLACE(SUBSTRING(ts.externalId FROM 14), '.Value', '')))

Thanks in Advance.
Please give suggestion for above issue