diff --git a/bitcoin/psbt.c b/bitcoin/psbt.c
index 2b9d13a0e..643a120cf 100644
--- a/bitcoin/psbt.c
+++ b/bitcoin/psbt.c
@@ -642,7 +642,7 @@ bool psbt_finalize(struct wally_psbt *psbt)
 		wally_psbt_input_set_final_witness(input, stack);
 	}
 
-	ok = (wally_psbt_finalize(psbt) == WALLY_OK);
+	ok = (wally_psbt_finalize(psbt, 0 /* flags */) == WALLY_OK);
 	tal_wally_end(psbt);
 
 	return ok && psbt_is_finalized(psbt);
diff --git a/external/libwally-core b/external/libwally-core
index 23e6b626c..9f2f42df3 160000
--- a/external/libwally-core
+++ b/external/libwally-core
@@ -1 +1 @@
-Subproject commit 23e6b626c8906bce2e3179409b938c9ef9bca463
+Subproject commit 9f2f42df357f5b76d6273ab3165fb9ca671841d8