Is it possible to share the packaged workbook (.twbx) file that you were working with showing the work done to this point? Also, please let us know the version of Tableau that you are working with. Someone may assist but in the process of doing so, they may upgrade your workbook to a version which you will not be able to open without updating yourself.
Here is a great reference page made by the members of our community regarding Workbooks. Packaged workbooks: when, why, how