Cumulative Total With Multiple Entries per Date

I have tried to use solutions from different threads but nothing solved my issue.

We need to show the cumulative total of the Sales - Purchases.

I have tried something like this

Cumulative Total = CALCULATE(
SUM('Table'[SALES-PURCHASES]),
FILTER(ALL('Date Table'),
'Date Table'[Date]<=MAX('Date Table'[Date])

but I am getting an error. I assumed it is because I have multiple entries per date.

The concept is like a bank statement or a cashflow.

I tried to use an index but I got this error.

I am attaching a dummy pbix here

for the dummy file, adding index is working fine. Dummy file consists of only 7 days. But when I used it in my original report, which has everything from 01/01/2019 up to today,

it is showing error.

Thank you