Why the exact same program runs differently on two different computer?

Question

I must have done something wrong with my computer. For some reasons, many program think the decimal separator is , instead of.

So I run this

'do stupid things
Dim c = System.Globalization.CultureInfo.DefaultThreadCurrentCulture
'Dim d = System.Globalization.NumberFormatInfo.NumberDecimalSeparator

Dim hello = JObject.Parse("{""volume"": 1.5}")
Dim hello1 = hello.Item("volume")
Dim hello2 = hello1.ToString
Dim d = Threading.Thread.CurrentThread.CurrentUICulture.NumberFormat.CurrencyDecimalSeparator
LogEvents("Result of Hello2 =" + hello2)
LogEvents("Threading.Thread.CurrentThread.CurrentUICulture.NumberFormat.CurrencyDecimalSeparator =" + d)
End ' end program

---

21/03/2022 17:34:27  Result of Hello2 =1,5
21/03/2022 17:34:27  Threading.Thread.CurrentThread.CurrentUICulture.NumberFormat.CurrencyDecimalSeparator =.

Curious, I run the exact program on another computer.

The result is

3/21/2022 6:09:06 PM  Result of Hello2 =1.5
3/21/2022 6:09:06 PM  Threading.Thread.CurrentThread.CurrentUICulture.NumberFormat.CurrencyDecimalSeparator =.

So for some unknown reason, there is a setting in my computer that makes program think the decimal separator is , instead of .

However, the value of Threading.Thread.CurrentThread.CurrentUICulture.NumberFormat.CurrencyDecimalSeparator is always "." in BOTH computers.

I wonder what settings I should have changed

Oh it turns out, in my computer hours are written in 24 hours format too. I wonder why?

If I go to control panel I see a settings where decimal separator is , instead of .

So I reset the whole settings. After resetting the decimal separator is still ,.

I have no idea why

I chose region english USA and english Indonesia. Decimal separator always ends up in comma.

I suppose I can change that manually to dot but why the hell it's default to comma in the first place?