Hosp Leave and Maternity Leave

Anyone’s company/HR rejected your HL applied and changed it to ML instead? Apparently my company does not accept HL if it’s applied right before ML. Ie if i apply HL on 1-7 Dec, ML on 8 Dec, my company will reject and indicate ML starts 1 Dec. Only will approve HL if there’s at least one day in between that I’m working. HR says it follows MOM law but can’t find any info on MOM website about this. Is this the correct way??