Federal tax return was rejected. IRS does not allow negative values on the Schedule C??

My electronic federal tax return was rejected.  The messages says that there are several amounts on the Schedule C for which the IRS does not allow negative values.  I imported information from Quickbooks and yes, the travel expenses has negative value because I spent some expense in 2019 and got paid by my client in 2020.  Because of that negative expense (relatively large), the total business expense is negative.  Just to fix this problem, I would like to modify and recognize some travel expenses reimbursed by a client as an income so that the total expense would become positive, but Turbotax does not allow me to change the travel expense number after importing it from Quickbooks.  I can modify other expenses, but not travel expenses.  Why?  How can I file the return electronically?