Sandbox

SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = 'BBDB-788Q-WWJD-M8CL-GU6X-VRXB-PI7I-1CSQ' 
  AND product_id = 40 
  AND expires_at > 1777203071 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}