LookUp Range Activity issue

Hi,

I found there’s something wrong with the activity “LookUp Range”

The activity sometimes go wrong that it couldn’t find the value which exactly existed in the Excel.
For example: I want to search “Material” in the Excel which is record in position A5.
In case I misunderstood, which is kinda impossible since the activity already being used for over 2 years in my project, I looped every cell in my Excel to check the “Material” whether exist or spelling incorrect, and it did exist in the file.

When I try to find the reason, I found that when I change the property Range of the LookUpRange activity, even smaller or bigger, it could truns out the different result that sometimes it can get the result of the correct position A5, sometimes it shows Null.
The only factor I changed above is the Range, so I believe this activity must has something bug exist.

I believe

Have you put the range parameter as “” so that it looks everywhere in excel?

Yes, that’s the original value of Range I set for the past 2 years.

And during the past it work perfectly.

This time since I got the new requirement so I update the project, but nothing change about this activity.