Interrupt not occur every time on w5500 INTn pin

hello,
I am not getting interrupt every time on INTn pin of W5500.
my code:
main()
{
w5500_init_fun();
wiz_Setup_Open(11000);
Set_Sn_IMR(0x04);
Set_SIMR(0x01);
Set_INTLEVEL(30);
Set_Sn_IR(0,0x00);
while(1)
{
if(external interrupt received)
{
process_received_data();
Set_Sn_IR(0,0x04);
external_interrupt_received=0;
}
}
}

Explain what exactly you want to have. You want interrupt for each byte received? What is being configured by int level 30?

See also Losing interrupts because SN_IR_RECV to SN_IR fails (silicon glitch?)