diff --git a/hypha/apply/stream_forms/blocks.py b/hypha/apply/stream_forms/blocks.py
index 5c709b5f7c..f912c00f16 100644
--- a/hypha/apply/stream_forms/blocks.py
+++ b/hypha/apply/stream_forms/blocks.py
@@ -420,7 +420,7 @@ class Meta:
 
     def get_field_kwargs(self, struct_value):
         kwargs = super().get_field_kwargs(struct_value)
-        kwargs['help_text'] = kwargs['help_text'] + f" Accepted file types are {settings.FILE_ACCEPT_ATTR_VALUE}"
+        kwargs['help_text'] = str(kwargs['help_text']) + f" Accepted file types are {settings.FILE_ACCEPT_ATTR_VALUE}"
         return kwargs
 
 
@@ -434,7 +434,7 @@ class Meta:
 
     def get_field_kwargs(self, struct_value):
         kwargs = super().get_field_kwargs(struct_value)
-        kwargs['help_text'] = kwargs['help_text'] + f" Accepted file types are {settings.FILE_ACCEPT_ATTR_VALUE}"
+        kwargs['help_text'] = str(kwargs['help_text']) + f" Accepted file types are {settings.FILE_ACCEPT_ATTR_VALUE}"
         return kwargs
 
     def prepare_data(self, value, data, serialize):