I suggest you to share details for a better solution.
According to my experience, if you use the excel activity a lot, I recommend you to use a kill before each use. Such errors can also be received when trying to open the other workbook without closing the full workbook.
Please check whether the file exists and the sheet1 present in it. Also check whether the file is corrupted .If all the above are correct, then try to downgrade or update the excel package and try to execute once.
As per my understanding the issue can be the version issue happened after the update of Uipath.