Who I have the same questioned this topic

I keep seeing the question regarding the roaming message when trying to make an outgoing call that states that the caller is now roaming and must call for a pin, can make a collect call, etc. But what I'm not seeing is an answer to the question. The responding reps want to know the zip code, etc., but no answer is given. I have an iPhone 8 and have been able to make outgoing calls from this area for several years. Clearly it's been a problem for many people for awhile.  Not being able to make a call is unacceptable and I need to know how to fix the problem. Help would be appreciated.