Hi Fabiano,
The option is there for me. In the UI I chose the Phone icon (calls) -> Phone details -> Entered the number and the option shows up after entering a number:

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James Dunn
Pitney Bowes Inc.
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Original Message:
Sent: 02-10-2023 04:14
From: Fabiano Benedetti
Subject: Where the option "Use the voicemail service of this external number"
Hello,
Documentation is mentioning here Forward your calls - Genesys Cloud Resource Center (mypurecloud.com), that in the "Forward my calls" option, we could configure an option called "Use the voicemail service of this external number" to allow GC to leave a message on the voicemail of the forward number.
We simply cannot find this option.
Thanks,
#Telephony
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Fabiano Benedetti
NTT Belgium NV/SA
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