The text file written on server using utl_file is appended with ‘FF’ at the end of each page in the file

I am creating a text file on the server and writing a message into the file using utl_file utility. The text file is created with ‘FF’ appended at the end of each page in the file. When this file is opened using Notepad++ it is seen as ‘FF’, when opened with Notepad, this is seen as a up arrow symbol.
Please help me get rid of this symbol.

Shared the code snippet, and the images of the symbol.[enter image description here] (https://i.stack.imgur.com/BRqBv.png)

I tried trimming the message before putting it into text file, however it did not remove the symbol.