Delete the beta 5 update.
Settings > General > iPhone Storage. It takes a while to load all the information, but you should see your Beta if you scroll down.
Restart the phone and ensure the beta is no longer showing in the storage.
Try downloading again. Give it a while. If it's not progressing, restart the phone. The progress should actually show it being half-way done. If it freezes again, restart. The progress bar will eventually complete.