Hi @bridges164 ,
(1) If you have already set the List rows present in a table to ISO 8601 (and this should work!), then you will need to try another method to convert the dates. The linked article in the previous post provides some options.

(2) Also check that the date column is set to a Date type in Excel then run the flow with the formatDateTime(item()['Event Start Date Time'],'yyyy-MM-ddTHH:mm:ss') expression

(3) I had instances where some dates would convert and had to resort to the expression to convert the dates.
Here is an extract of the output of a demo flow using the following expression:
addDays('1899-12-30', int(item()?['DateAccessGranted']), 'dd-MM-yyyy')

{
"Name": "Catherine Le",
"Date": "44854",
"ConvertedDate": "20-10-2022"
},
{
"Name": "Christopher Le",
"Date": "44854",
"ConvertedDate": "20-10-2022"
},
{
"Name": "Martin Smith DDS",
"Date": "44854",
"ConvertedDate": "20-10-2022"
},
{
"Name": "Stacy Rodriguez",
"Date": "44854",
"ConvertedDate": "20-10-2022"
},
{
"Name": "Kayla Miller DVM",
"Date": "44854",
"ConvertedDate": "20-10-2022"
},
{
"Name": "Kendra Rogers",
"Date": "44854",
"ConvertedDate": "20-10-2022"
},
{
"Name": "Michael Young",
"Date": "44498",
"ConvertedDate": "29-10-2021"
},
{
"Name": "Bruce Johnson",
"Date": "44495",
"ConvertedDate": "26-10-2021"
Ellis
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