First you should have filled in a W-220 so no WI taxes are withheld :
https://www.revenue.wi.gov/TaxForms2017through2019/w-220.pdf
Reciprocal state rules : https://ttlc.intuit.com/turbotax-support/en-us/help-article/state-taxes/states-reciprocal-agreements...
Next you need to send in quarterly IL estimated payments : https://www.officialpayments.com/pay-illinois-taxes.jsp
