Android Question Calling in hidden mode

What happens when you send the string with *31#?

Hello
Thank you EREL for your answer.

By using :
Ntel="#31#" & Ntel
StartActivity(LV.p.Call(Ntel))
the answer is in file 01
Appel non envoyé. Numéro saisie invalide --> Call not sent. Invalid entered number

By using :
Dim Ph As Intent
Ph.Initialize(Ph.ACTION_CALL, Ntel)
StartActivity(Ph)
the answer is in file 02
Yours sincerely
FerGeoRi

In France :
If you want to hide your phone number from your cell phone for a specific call, you just have to dial #31# before the number of your correspondent. Thus, the person you are calling will not be able to see your number, you are calling in unknown mode.

To hide your phone number from the person you are calling (masked call), precede their phone number with #31#. For example, if you want to call 0102030405, type: #31#0102030405.

Does this link help at all? https://alvinalexander.com/android/how-make-phone-call-from-android-app-phone-dialer-intent/
It seems to include some things you don't do.

1. Please use [code]code here...[/code] tags when posting code.
2. Try:

Good evening
Thanks to MikeSW17 for your response.
And especially thanks to Erel because his solution works very well.
I would never have found it without you.
Thanks again.
Best regards.
FerGeoRi