INSERT Permission Denied

Howdy,

I have an INSERT:

that's failing with permission denied on the schema:

ERROR:  permission denied for schema treg
LINE 1: SELECT 1 FROM ONLY "treg"."cd_combined_offices" x WHERE "com...
                           ^
QUERY:  SELECT 1 FROM ONLY "treg"."cd_combined_offices" x WHERE "combined_office_id" OPERATOR(pg_catalog.=) $1 FOR KEY SHARE OF x

Table structure:

csbstage=# \d+ treg.cd_combined_office_mappings
                                             Table "treg.cd_combined_office_mappings"
       Column       |         Type          | Collation | Nullable | Default | Storage  | Compression | Stats target | Description
--------------------+-----------------------+-----------+----------+---------+----------+-------------+--------------+-------------
 tcsi_office_id     | character varying(15) |           | not null |         | extended |             |              |
 combined_office_id | numeric(38,0)         |           | not null |         | main     |             |              |
 sb2_account_id     | integer               |           | not null |         | plain    |             |              |
 postal_code        | character varying(15) |           | not null |         | extended |             |              |
 category           | character varying(20) |           | not null |         | extended |             |              |
 account_name       | character varying(50) |           | not null |         | extended |             |              |
 city               | character varying(50) |           | not null |         | extended |             |              |
 state              | character(2)          |           | not null |         | extended |             |              |
 is_preferred       | character(1)          |           | not null |         | extended |             |              |
 is_closed          | character(1)          |           | not null |         | extended |             |              |
 is_parent          | character(1)          |           | not null |         | extended |             |              |
Indexes:
    "cd_combined_office_mappings_pkey" PRIMARY KEY, btree (tcsi_office_id)
    "idx_combined_mappings_1" btree (combined_office_id)
    "idx_combined_mappings_2" btree (sb2_account_id)
Foreign-key constraints:
    "cd_combined_mappings" FOREIGN KEY (combined_office_id) REFERENCES treg.cd_combined_offices(combined_office_id) NOT VALID
Publications:
    "csbstage_postgres_to_oracle"
Replica Identity: FULL
Access method: heap

The user has all required privileges from what I can tell.  The postgres user even gets the same failure when running the INSERT.  Would anyone be able to give any advice here, please?

Thanks,

Sam
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