Raids keep getting stuck at 1 raider remaining

Almost every single time I trigger a raid and go through with it, there will always be one wave where 1 or two raiders are remaining and they wont appear absolutely anywhere for an upwards of 10 minutes until they finally arrive to the village.

What I expected to happen was...:
I expected raids to be quick and streamlined.

What actually happened was...:
They weren't because of this bug.

Steps to Reproduce:
1. Trigger a raid.