PowerPoint slide progression problems when using Screen Sharing on Zoom

At our last weekly hybrid meeting the remote attendees could not see the PowerPoint slides advance when we were screen sharing a Powerpoint presentation. We were projecting the same PPt presentation on a screen at the meeting at the same time. Those at the in person meeting could see the slides advance. Those on Zoom saw the first slide during the entire presentation and no subsequent slides. We are using MS Office 365 and this is the first time this has happened. We have managed quite a few hybrid meetings where we screen shared PowerPoints in the past and this did not occur. Anyone seen this problem before? If so where do we need to look to correct this for our next weekly meeting? We had 3 different PPts cued up and this same issue occurred with all of them.