Not Working - Update record using deluge

I have created a function which checks date greater than 31st March'21 and if true, sums the values

I am trying to update the sum value in a currency field i created but it is not updating for whatever reasons,

Help :D

sum = 30;

Custom_date = '31-Mar-2021';

if(CORR1Date > Custom_date)

{

sum = sum + CORR1Amt;

}

if(CORR2Date > Custom_date)

{

sum = sum + CORR2Amt;

}

if(CORR3Date > Custom_date)

{

sum = sum + CORR3Amt;

}

update = zoho.crm.updateRecord("Deals",potid,{"CORtotal":sum});