SMS text to remind not being delivered to patients

We have had an ongoing problem with our SMS appointment reminders not being delivered to patients. The system shows they have been delivered but they are not being received . After many conversations with the help team it remains unresolved. Our SMS credits continue to be spent with nothing delivered .

Has anyone else had this issue and how did you resolve it.

Many thanks

Hey Anne,

Thanks for this.
Can you please reach out on the chat to me so that I can check this out.