Predicate operator 'AND' doesn't work in loading job

I am trying to load data from JSON file to my graph and I have more than 1 conditions on loading data to vertex. I used operator AND for it, but it doesn’t work, next error occurs:
Encountered " “and” "AND “”

Was expecting one of:

";" ...

"," ...

"option" ...

"using" ...

Here is example. I need two condition: value must be not empty and value must not be equal to “Unknown”

LOAD input_file TO VERTEX example
VALUES (gsql_concat(“name_”, "value"), "name", “value”)
WHERE gsql_is_not_empty_string("value") AND “value” != “Unknown”
USING JSON_FILE=“true”;

I tried also another variant of WHERE clause, but error was the same.
WHERE gsql_is_not_empty_string("value") AND (NOT (gsql_token_equal(“value”, “Unknown”)))

Please try as below:

LOAD input_file TO VERTEX example
VALUES (gsql_concat(“name_”, "value"), "name", “value”)

WHERE "value" != "" AND “value” != “Unknown”
USING JSON_FILE=“true”;

Best Regards,