Diplomacy was hard in the ancient world.
“On the diplomatic side, yes, Imperator in its deviations from the EUIV model captures something real about the ancient world, which is, quite simply, the relatively primitive and disconnected state of diplomacy in it. Compared to diplomacy in the early modern period, ancient diplomatic relations both struggled with remarkably more limited information and a shockingly blunt diplomatic language oriented around compellence rather than persuasion.”
https://acoup.blog/2024/07/19/collections-teaching-paradox-imperator-part-i-divisa-in-partes-tres/