when tried to upload upto 26 mb file in voice broadcast then, validation message not displayed

Steps :- 

1. Login as admin.
2. install voice broadcast ad-don.
3. re login as admin.
4. now go to services > voice broadcast.
5. click on create.
6. now enter valid details or select valid csv file.
7. now select 26 mb size of wav file from local.
8. now click on save and observe.

Actual result :- when tried to upload upto 26 mb file in voice broadcast then, validation message not displayed

Expected result :- there should be display validation message.

se videos :-