I have CTE based SUBQUERY block named “sq_filter” which returns below kind of jsons

{
  "aId": "2769ba8f",
  "bId": "5837c902",
  "tn": "oi"
}

I want to update collection named “xyz” containing below kind of documents

{
  "blocks": {
    "down": [
      {
        "dId": "bd8e20c9",
        "cti": "dd",
        "len": 111
      }
    ],
    "up": [
      {
        "bId": "5837c902",
        "cti": "bb"
      },
      {
        "bId": "d322701d",
        "cti": "bb"
      }
    ]
  },
  "aId": "2769ba8f",
  "cti": "aa",
  "tn": "oi"
}

Given above two items, I want to write update query for collection “xyz” which finds matching “xyz”.”tn” = “sq_filter”.”tn” and “xyz”.”aId” = “sq_filter”.”aId” from collection “xyz”, and remove matching “sq_filter”.”bId” from “blocks”.”up” array

Below is my query.

WITH abc AS (
...
),
sq_filter AS (
...
)
UPDATE xyz AS x
SET x.blocks.up = ARRAY v FOR v IN x.blocks.up WHEN v.bId != (SELECT sf.bId FROM sq_filter AS sf WHERE x.tn = sf.tn AND x.aId = sf.aId) END
WHERE x.cti = "aa"
;

Expectation post update of said document from “xyz” collection, which is removal of one element from “blocks”.”up” array which is matching sq_filter’s bId

{
  "blocks": {
    "down": [
      {
        "dId": "bd8e20c9",
        "cti": "dd",
        "len": 111
      }
    ],
    "up": [
      {
        "bId": "d322701d",
        "cti": "bb"
      }
    ]
  },
  "aId": "2769ba8f",
  "cti": "aa",
  "tn": "oi"
}

I am getting below syntax error

syntax error - line **, column 1, at: UPDATE (reserved word)