Texts not sent - carrier error

[Wooster2025]

My wife and I both use different 'third party' network providers, who are (both) EE MVNO. We both have different makes of phone, but are both Android. Recently, we are both getting a lot of texts 'not sent'. We're both on PAYG and it's irritating to be charged for a text not being sent! We both (initially) used Google Messenger and I've recently moved to Fossify. We've used our phones in the KT19 and RH12 postcode areas. Both have a good 4G signal - 3 or 5 bars out of 5. Both phones have been switched off (for hours) before we've tried again. I've cleared the cache on my phone. Nothing has changed. 9 out of 10 texts are 'Not Sent. Carrier Error'. 

Our network providers say they can't see anything wrong.  All (for example) 10 texts I sent to the same number within a few minutes ('Not Sent. Carrier Error. Options: Cancel or send again' So I send again) are just seen as 10 billable texts. 

I had been with Tesco Mobile (O2) for decades and never had a problem.

Does anyone have any suggestions?

[XRaySpeX]

Do you both have enough credit or text allowances to cover sending texts?

Aside from that this is something you'll have to take up with your networks. It is their service, not EE's.

[Northerner]

Hi @Wooster2025 

It seems to be Fossify which is the issue if this started when you used this messenger service. Have you checked your settings.

Thanks 

[Wooster2025]

Thanks for the quick response.
It doesn't matter weather I use Google Messenger or Fossify. And my wife
has always used Google messenger. We both get the same error message.

[Wooster2025]

Thanks for the quick response. If it the carriers fault, why would two
separate carriers have the same issue? The only common denominator is EE.