There isn't now nor ever has been an ability to claim €3.20 a day.
Your employer may pay you €3.20 a day tax free.
If they don't,you may claim 10% of your electricity and gas bills and 30% of your broadband bill as a tax credit.
However,this is apportioned by the number of days actually worked from home.
So,let's say energy bills 2k,and bb 700 and 80 days wfh.
So 2k*10%*80/365(43.80) and 700*30%*80/365(46.00)
89.80 @40% =€35.92 refund.
Adjust the figures to suit,but in all honesty,it's barely worth it.
I don't know,but I'd guess you could only claim half if 2 of you are wfh.