Car & Truck Expenses Worksheet: Cost must be entered

"schedule C -- Car & Truck Expenses Worksheet: Cost must be entered."

 

Hi everyone, I almost complete my tax return but at the end the program asked me to entered my vehicle cost. There are an empty box next to the question and I need to enter a number before I can file my tax return electronically. I need help finding this number for my 2019 tax return.