1080p uploads not streamable as 1080p


I have uploaded a set of screen recordings, that had an original screen resolution of 1080p, yet after processing, the maximum streaming resolution is 720p.
Why is this, and how do I get 1080p as a streaming option? Was the original bitrate too low? (these are screen recordings so bitrate is relatively low, and it seems nonsensical to artificially force the bitrate higher).