It shows I am still connected to the Network with a good signal, however all calls I try to make fail, texts are showing not delivered and I cannot receive calls or texts?
How do I start problem solving this?
If the problem is not a service/SIM issue @brianmcintyre , does mobile data work (i.e. not WiFi).
I ask since a phone which has been blacklisted will not operate for calls and texts, but will for mobile data. Unscrupulous sellers have been known to, once they have sold on a used phone, declared it lost/stolen in order to claim on insuarance, resulting in the phone becoming blacklisted.
Hopefully this does not apply to you.
"Never attribute to malice that which is adequately explained by stupidity." - Hanlon's Razor