Hello Statalists!

I've been using STATA's merge function for a while, but this is something I've never encountered, so I was just wondering if anyone has any idea what should be done to solve the problem?

So here's the issue: I was trying to merge data2 to data1 on two variables ID1 and ID2; both data files and the do file were saved in the same folder. My command was:

merge 1:1 ID1 IDs using data2

After running the command, I got an error message:

file data2.dta not found
r(601);

I triple checked the file name and the directory and they were all correct. This was supposed to be an easy fix but I just couldn't figure out what was going on. Has anybody experienced anything similar to this issue? Any ideas would be greatly appreciated. Thank you so much in advance!

P.S. I'm using STATA 15.1