Your job title is not the deciding factor here, but rather what you actually do. For example, NOC 1225 is specific for purchasing agents and officers, i.e. specialists who purchase good or services for an entity. A purchasing agent would negotiate contracts with suppliers; just administering contracts internally would not support that.
If, when perusing your detailed job description, you find that it matches the Main Duties write-up in a NOC group, that's the one to use (if eligible for CEC).
If you are still unsure after going through that exercise, feel free to post your job description here. Folks here will surely chime in with their opinion.