Inconsistencies:
As per Zulip discussion
A hyphen should be used for the field and dot (.) should be used for component; hence
OBX.21, OBR.22, MSH.7, OBX.15, OBX.2, OBX.5, OBX.6, NTE.3, OBX.7, OBX.2, OBX.5, OBX.6 & OBX.7 should all have a hyphen instead of a dot(.).