Hi @kingorhu,
Yes, this can happen with some numbers.
Although 0789 numbers are normally standard UK mobile numbers, certain services can be classified differently depending on how they're configured, which may result in them being treated as an out-of-plan or chargeable service.
You can read more about chargeable and out-of-plan services here: https://www.idmobile.co.uk/help-and-support/call-charges
If you're unsure why this particular number is being flagged as chargeable, we'd recommend contacting our Customer Service Team via Live Chat so they can investigate further.
Regards,
Gemma M
The iD Mobile Social Media Team
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