The root partition " / " can not take more than a specific size

<img src="/sites/profiles/files/discussion/images/2022-03/fdssdfdsfsd.jpeg" width="1280" height="856" alt="test" title="test" />Hello, I am new to RedHat
I tried to install RedHat 8.5, but when I tried to give / " /root" partition 53GiB it only took 38.66GiB as shown in the picture.
I tried changing Device Type and File System to ext4 but nothing changed, I tried to create /root partition first but no results. It only takes 38.66 GiB which is insufficient for me!
And even if I chose automatic partitioning, it stays the same, /root partition does not take more than 38.66 GiB.

If you know anything that could help me, I will much appreciate it.

Thank you

<img src="/sites/profiles/files/discussion/images/2022-03/fdssdfdsfsd.jpeg" width="1280" height="856" alt="test" title="test" />