Create a barebones letsyncrypt.ini (with TOSAgreed = false), to resolve that

FAQ.

ctrl/letsyncrypt.ini

+; $Id$
+; For use with exec/letsyncrypt.js
+; See http://wiki.synchro.net/module:letsyncrypt for details
+
+Host = acme-v02.api.letsencrypt.org
+Directory = /directory
+TOSAgreed = false
+GroupReadableKeyFile = false
+
+[Domains]
+
+[key_id]
+
+[State]