Follow this tutorial below to set up Beautify to work correctly with HDRP:
Beautify HDRP - Installation Guidline
Step 1: Make sure you have the latest version of the HDRP package. Head over to package manager, and download the latest version. Then install it.
Step 2: Make sure you have the HDRP asset assigned in the Graphics value, if not, create and add a new one, or head over to Beautify – HDRP Settings folder, and add the ready-to-use asset located there.
Step 3: Add Beautify HDRP to the “After Post-Processing” list in HDRP Default Settings.
Step 4: Now you can add Beautify to a post-processing volume, set its intensity to 1, and start using its features!