You can try to set HandleLidSwitch=ignore event defined in /etc/systems/logind.conf. That will definitely prevent the laptop from sleeping on lid close. It might also prevent the laptop from waking on lid open.
Regardless, I suggest hunting down what broke that setup recently. Its probably some new daemon is responsible for configuring those events in a less arcane way.
1GiB = 1024MiB and 1GB = 1000MB. OP does seem to get those confused.