Sandbox

SELECT 
  1 
FROM 
  cscart_june_setupec_print_temp_designs 
WHERE 
  session_id = '9MUF-UBSK-U65C-R3DW-GQ4X-3UUU-RDMD-IN40' 
  AND product_id = 106 
  AND expires_at > 1781894233 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00033

JSON explain

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