Agent is not working for Pg VectorDB

[Hkudumu]

CREATE MODEL chat_model
PREDICT text
USING
engine = "litellm",
model = "azure/gpt-4.1",
base_url = "",
deployment_id = "",
api_key = "**********",
prompt_template = 'Answer the user input in helpful way: {{questions}}',
temperature = 0;

CREATE SKILL pgvectordb_3
USING
type = 'text2sql',
database = 'pgvector_datasource',
tables = ['public.upsertion_record'],
description = "This is user infos data";

CREATE AGENT pg_agent
USING
model = 'chat_model',
skills = ['pgvectordb_3'];

SELECT * FROM pg_agent WHERE question= "hi";

When I am running the select query from the agent getting below error

"None of [Index(['questions'], dtype='object')] are in the [columns]"