diff --git a/demos/fuzzer_builtin/main.tscn b/demos/fuzzer_builtin/main.tscn
index 21b4c83..0461c5a 100644
--- a/demos/fuzzer_builtin/main.tscn
+++ b/demos/fuzzer_builtin/main.tscn
@@ -660,7 +660,7 @@ func _fuzz_tlattributedshapedstring():
 		if randi() % 3 == 0:
 			str1.set_base_font(_fuzz_tlfontfamily())
 		else:
-			str1.set_base_font(nt_fam_full[randi() % (nt_fam_full.size() - 1)])
+			str1.set_base_font(nt_fam_full)
 		str1.get_base_font();
 
 		if randi() % 3 == 0:
@@ -787,7 +787,7 @@ func _fuzz_tlshapedstring():
 		if randi() % 3 == 0:
 			str1.set_base_font(_fuzz_tlfontfamily())
 		else:
-			str1.set_base_font(nt_fam_full[randi() % (nt_fam_full.size() - 1)])
+			str1.set_base_font(nt_fam_full)
 		str1.get_base_font();
 
 		if randi() % 3 == 0:
diff --git a/demos/fuzzer_gdnative/main.tscn b/demos/fuzzer_gdnative/main.tscn
index 4293104..090be14 100644
--- a/demos/fuzzer_gdnative/main.tscn
+++ b/demos/fuzzer_gdnative/main.tscn
@@ -611,7 +611,7 @@ func _fuzz_tlattributedshapedstring():
 		if randi() % 6 == 0:
 			str1.add_attribute(randi() % RANGE - RANGE / 2, _randintarray(), randi() % RANGE - RANGE / 2, randi() % RANGE - RANGE / 2)
 		if randi() % 2 == 0:
-			str1.add_attribute(TLConstants.TEXT_ATTRIBUTE_FONT, _fuzz_tlfontfamily(), randi() % RANGE - RANGE / 2, randi() % RANGE - RANGE / 2)
+			str1.add_attribute(1, _fuzz_tlfontfamily(), randi() % RANGE - RANGE / 2, randi() % RANGE - RANGE / 2)
 		if randi() % 3 == 0:
 			str1.remove_attribute(randi() % RANGE - RANGE / 2, randi() % RANGE - RANGE / 2, randi() % RANGE - RANGE / 2)
 		str1.has_attribute(randi() % RANGE - RANGE / 2, randi() % RANGE - RANGE / 2)
@@ -669,7 +669,7 @@ func _fuzz_tlattributedshapedstring():
 		if randi() % 3 == 0:
 			str1.set_base_font(_fuzz_tlfontfamily())
 		else:
-			str1.set_base_font(nt_fam_full[randi() % (nt_fam_full.size() - 1)])
+			str1.set_base_font(nt_fam_full)
 		str1.get_base_font();
 
 		if randi() % 3 == 0:
@@ -796,7 +796,7 @@ func _fuzz_tlshapedstring():
 		if randi() % 3 == 0:
 			str1.set_base_font(_fuzz_tlfontfamily())
 		else:
-			str1.set_base_font(nt_fam_full[randi() % (nt_fam_full.size() - 1)])
+			str1.set_base_font(nt_fam_full)
 		str1.get_base_font();
 
 		if randi() % 3 == 0:
diff --git a/src/resources/tl_shaped_attributed_string.cpp b/src/resources/tl_shaped_attributed_string.cpp
index 49a63c4..c8b893a 100644
--- a/src/resources/tl_shaped_attributed_string.cpp
+++ b/src/resources/tl_shaped_attributed_string.cpp
@@ -1279,14 +1279,14 @@ int64_t TLShapedAttributedString::get_attribute_start(int64_t p_attribute, int64
 	}
 	if (p_attribute <= TEXT_ATTRIBUTE_MAX_FORMAT_ATTRIBUTE) {
 		auto attrib = format_attributes.find_closest(p_index);
-		if (attrib) {
+		if (!attrib) {
 			ERR_PRINTS("Attribute not set");
 			ERR_FAIL_COND_V(true, -1);
 		}
 		return attrib->key();
 	} else {
 		auto attrib = style_attributes.find_closest(p_index);
-		if (attrib) {
+		if (!attrib) {
 			ERR_PRINTS("Attribute not set");
 			ERR_FAIL_COND_V(true, -1);
 		}
@@ -1302,16 +1302,24 @@ int64_t TLShapedAttributedString::get_attribute_end(int64_t p_attribute, int64_t
 	}
 	if (p_attribute <= TEXT_ATTRIBUTE_MAX_FORMAT_ATTRIBUTE) {
 		auto attrib = format_attributes.find_closest(p_index);
+		if (!attrib) {
+			ERR_PRINTS("Attribute not set");
+			ERR_FAIL_COND_V(true, -1);
+		}
 		attrib = attrib->next();
-		if (attrib) {
+		if (!attrib) {
 			ERR_PRINTS("Attribute not set");
 			ERR_FAIL_COND_V(true, -1);
 		}
 		return attrib->key();
 	} else {
 		auto attrib = style_attributes.find_closest(p_index);
+		if (!attrib) {
+			ERR_PRINTS("Attribute not set");
+			ERR_FAIL_COND_V(true, -1);
+		}
 		attrib = attrib->next();
-		if (attrib) {
+		if (!attrib) {
 			ERR_PRINTS("Attribute not set");
 			ERR_FAIL_COND_V(true, -1);
 		}