Define what the conversation is for
Name the two or three questions, practical issues, or acknowledgments you hope to cover. Do not call it closure when the real aim is to restart the relationship.
Put limits around the request
Offer a short duration and options such as phone, message, public place, mediator, or no conversation. Say explicitly that you will accept no response as a no.
Create closure that does not require access
Write unsent answers, speak with a trusted person, or use counseling if they decline. Never bypass a block, court order, safety plan, or repeated refusal to obtain a conversation.