Not sure if where you live, and if they are doing LTE upgrade in your area, but I normally get that when I'm in the border of 3G and 4G LTE zones, I just get it once and then I can resend and goes through. It is a network error.
You can upgrade your settings, in Android, go under settings - system updates - upgrade PRL and upgrade profile (do one at a time).
That should help, but give us more info, like: location and does this happen when you are close to Airave or not, etc.
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