SELECT 
  1 
FROM 
  cscart_aprilec_print_temp_designs 
WHERE 
  session_id = '01OM-U7B8-NV60-BQIP-Y1GC-5M2D-FGQC-HMYY' 
  AND product_id = 120 
  AND expires_at > 1777123962 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00036

JSON explain

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