Hard for us to know for sure without more information. But the error message says the process was killed - in most cases, and I would assume it's the same reason here, it's because the job uses more memory or resources (e.g. runtime) than what it is allowed to by the job scheduler.
Check your cluster information page/wiki on how to configure job submission, you can typically configure your jobs to send you an email if the job fails or is stopped with the reason for why it was done. Otherwise ask your cluster admin.
To reduce memory you can try a few things:
- Increase the number of OpenMP threads and reduce the number of MPI processes accordingly
- Increase the number of processes per k-point or "processes per <task>" for operations that allows multilevel parallelism
- Decrease settings that have a big impact on memory usage, e.g. basis set size, grid size, etc
