SELECT 
  1 
FROM 
  cscart_june_setupec_print_temp_designs 
WHERE 
  session_id = 'ZQJS-YL8O-S8LD-NUPT-4C5I-Y638-7ZGS-M03Q' 
  AND product_id = 88 
  AND expires_at > 1781763194 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00020

JSON explain

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