You are falling victim to this: https://forum.seafile.com/t/error-on-seafile-docker-upgrade-13-0-15-core-dump-because-of-numpy/24870/4 See the Illegal instruction (core dumped) errors in seafile-monitor.log. Running on a rather old cpu?
For a quick fix, manually install the older v.13.0.12, though I don’t know the downsides of this. Also there is a fix for the newer version in the thread above, however it’s more complicated.