SharePoint Power Automate - Excel to List

Description

if someone can provide the solution in their reply, I will test and if successful I will award the job and release amount.
Scenario:I have an excel document which automatically updates a SharePoint list via power automate.The excel document and list both have 3 columns, Title, Course Status, Last Completed (this is a date).All works fine to update or create a SharePoint item when the ‘Course Status’ column and ‘Last Completed’ column have data in excel.
The initial problem I had (now partially resolved), was when the ‘Course Status’ column in excel had data but the ‘Last Completed) column in excel was blank, I was getting an error message when running the flow regarding the blank columns and then the list would not update correctly as the row value for ‘Last Completed’ was blank.
I still needed the list the pick up the ‘Course Status’ information and leave the ‘Last Completed’ blank in the list to mirror the excel sheet. To resolve this, in the Update Item and Create Item actions, I changed the mapping of ‘Last Completed’ to an expression instead of linking it directly to the excel column. The expression is:if(equals(item()?['Last Completed'],''),null,item()?['Last Completed'])
This partly solved my solution.
What now happens is when I first run the flow, it runs successfully and the list will include all the correct data (this includes ‘Course Status’ with or without the ‘Last Completed’ column which is what I need). However the problem I have is when I run the flow again, the ‘Last Completed’ column in the list removes the date for ALL entries, and if the ‘Course Status’ column does not update at all, even though this has changed on excel. It seems after running the same flow the second time or more, it is still only shows the same Course Status column with no changes, and the Last Completed column is blank for all entries when it should be full and only missing a few dates.
I have attached 2 screenshots of how the list displays on the first flow run (exactly what I need it to do every time I run it), and then the second time I run the flow (Course Status doesn’t update, and the date is removed for all entries in Last Completed).
I have also attached the current flow.
Please assist, if someone can provide the solution in there reply I will test and if successful I will award the job and release amount.