18 Unknown 'international text message' charges

[BSC]

This month's bill contains 'additional charges' of £8.10, which once I downloaded the bill is a total of 18 charges of 0.45p for 'international text messages'.  No dates listed, only my mobile number listed next to them.  I have no idea what these refer to--any ideas?

I have an iPhone and regularly use it for imessages with my family in the US.  Have done so for years with none of these strange charges appearing; have not traveled in the time of the billing period. 

I send plenty of pic messages, and can track the relevant pic message charges in another part of the bill, which leaves me confused as to what, exactly, these 'international text message' charges are--and all the more confused given there's not even a listed number as recipient.  Anyone come across something like this before or have an idea of what it could be?  Worth calling? I'm trying to avoid losing too much time in my day.

Thanks!

[MI5 · Accepted solution]

@BSC 

The only thing I can think that might have happened is if iMessage failed at either end and the message was sent as an SMS. Are any of the messages in your thread "green" rather than "blue"?

Other than that a call to CS is the only option.

If you call 202 around 8.00am you should get through quickly though......

[EmilieT]

Hi @BSC, did the above suggestions help you underestand better what happened? If you need to get in touch with Customer Service to understand the charges, just to add, you can find all ways to contact O2 and get help in our Guide: How to find help & contact O2