I still don't post to Ireland.
My experience is not recent but there are still posts in the forum from time to time from sellers who have issues with getting items through customs even though all the paperwork is correct.
When I had a 'not delivered' claim and investigated it with AnPost, I was told the item was 'being returned' (to me) because 'it has been delivered'.
I had a long, frustrating, surreal online chat with a customer services person at AnPost who did not understand that the parcel could not actually be on its way back to me if it had been delivered.
Never again!
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)