I don't know why it is stalling.
What I can suggest, is reboot to a live usb then zap the partitions using dd. And by zapping I mean zapping - there is no partition table - no anything when you do it this way.
That also means that you need to be observant and double check the command I am giving you.
First open a terminal and identify your disks - you could get an output like this
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 223,6G 0 disk
├─sda1 8:1 0 300M 0 part /boot/efi
├─sda2 8:2 0 512M 0 part /boot
├─sda3 8:3 0 32G 0 part [SWAP]
└─sda4 8:4 0 190,8G 0 part /
sdb 8:16 1 7.3G 0 disk
└─sdb1 8:17 1 7.3G 0 part
It is obvious - I hope - which one is the live media and which one is the system disk.
Replace the letters in the command with the letters representing your system disk
sudo dd if=/dev/zero of=/dev/sdX bs=1M count=10
The command writes 10MiB zeroes to your system disk
Then start the installer.