Can I change my method of payment after I’ve already filed taxes?

Unfortunately, no. If your return has been submitted you would not be able to change your method of payment. Per the IRS: If the return hasn't already posted to our system, you can ask us to stop the direct deposit. 

Please see the IRS link below for more information:

IRS Frequently Asked Questions

Is there a specific number I can contact? I’ve been contacting the IRS but the automated voice systems does not ask about by situation.

Try this link. How do I contact the Internal Revenue Service (IRS)? How to contact the IRS

I appreciate the help, but I have been told that there is no such thing as stopping a direct deposit while my return is pending. Thank you.