Since "1080p" usually refers to high-definition releases, you need a subtitle track that matches that specific version's timing. Recommended sites include:
If the text appears before or after the dialogue, you can fix the delay in your media player: How to Sync Subtitle SRT Files with Videos subtitle Outlaw King 1080
YIFY Subtitles: Ideal if your 1080p file is a "YIFY" or "YTS" release, as these are pre-synced for those versions. subtitle Outlaw King 1080