diff --git a/add-patch.c b/add-patch.c
index 447e8166d24f43..0997d4af7398a2 100644
--- a/add-patch.c
+++ b/add-patch.c
@@ -1668,7 +1668,7 @@ static int patch_update_file(struct add_p_state *s,
 			}
 		} else if (s->answer.buf[0] == 'p') {
 			rendered_hunk_index = -1;
-		} else if (s->answer.buf[0] == '?') {
+		} else {
 			const char *p = _(help_patch_remainder), *eol = p;
 
 			color_fprintf(stdout, s->s.help_color, "%s",
@@ -1692,9 +1692,6 @@ static int patch_update_file(struct add_p_state *s,
 				color_fprintf_ln(stdout, s->s.help_color,
 						 "%.*s", (int)(eol - p), p);
 			}
-		} else {
-			err(s, _("Unknown command '%s' (use '?' for help)"),
-			    s->answer.buf);
 		}
 	}
 
diff --git a/t/t3701-add-interactive.sh b/t/t3701-add-interactive.sh
index ed7e414649ca1d..04d833337342cf 100755
--- a/t/t3701-add-interactive.sh
+++ b/t/t3701-add-interactive.sh
@@ -8,8 +8,6 @@ TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-terminal.sh
 
-SP=" "
-
 diff_cmp () {
 	for x
 	do
@@ -58,19 +56,6 @@ test_expect_success 'warn about add.interactive.useBuiltin' '
 	done
 '
 
-test_expect_success 'unknown command' '
-	test_when_finished "git reset --hard; rm -f command" &&
-	echo W >command &&
-	git add -N command &&
-	git diff command >expect &&
-	cat >>expect <<-EOF &&
-	(1/1) Stage addition [y,n,q,a,d,e,p,?]? Unknown command ${SQ}W${SQ} (use ${SQ}?${SQ} for help)
-	(1/1) Stage addition [y,n,q,a,d,e,p,?]?$SP
-	EOF
-	git add -p -- command <command >actual 2>&1 &&
-	test_cmp expect actual
-'
-
 test_expect_success 'setup (initial)' '
 	echo content >file &&
 	git add file &&
@@ -247,6 +232,7 @@ test_expect_success 'setup file' '
 '
 
 test_expect_success 'setup patch' '
+	SP=" " &&
 	NULL="" &&
 	cat >patch <<-EOF
 	@@ -1,4 +1,4 @@