Welcome to the Community Forum, apologies for the delay in getting back to you.
I've checked with our Mobile Team on this and generally speaking, there should be no problem with using 08 numbers unless you are using a call service. We would need to look into this specifically for you, so give us a call on 789 or 0345 6000 789 so that we can clear account security with you and see who notified you of this and why.
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