System update was interrupted, followed steps mentioned in a solution thread to a similar issue but now the system does not boot up

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4

Try to change to text console with CTRL+ALT+F2 and log in there. If that works, try to follow this guide to provide good information about your system: How to provide good information

Just to be sure, probably it is a good idea to update the system:

pamac update

Also, you probably are going to need to look for errors in the journal:

journalctl -b -xe

You can move in the journal with cursor keys and/or PageUp/PageDown keys. Journal can be quite large. You can quit the journal with q.

To restart your computer execute reboot and to power off execute poweroff.