From like two days ago, when I send txt msgs to my parents in China, they can no longer receive them. I put my SIM card in my friend's phone they still cannot receive my msgs. Then my friend used her SIM card to send msg to my parents and this time they receive it. So I guess it's my SIM card's problem, but I used to send international txt msgs to them since last year and almost no problem (although sometimes they were not able to receive but it happened really rarely).
Sending msgs to other Fido & Rogers & Bell users are good, just international msgs. By the way, the service provider's name of my parents' phone is China Mobile.
Thank you ahead for answering!
***Edited to add labels***
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