When I try to make calls from my phone book I cannot dial out. My phone tells me I have either dialled an incorrect number or do not have enough credit. If I dial the number n manually I can make the call
I hope this helps. I've seen a number of posts in the past which may be related to your problem.....it often involves an iphone and dial assist issues.
From a Home screen on your iPhone tap Settings > Phone > Dial Assistswitch toturnon oroff.
One of the other fixes is to go to Setttings / General / Language and Region and change the Region to Belgium, even it was saying UK and then back to UK.
If it's an android phone then you should look for Dial Assist/ Assisted Dialling in the settings and turn it off. It's difficult to say where it is on an android as they all have different settings layouts, but you could probbaly do a google search or check the phone's manual
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