How to playback audio recorded on microsoft word help please!!

I have been recording my history class while i take notes on my macbook on microsoft word and in the past i have been able to click on the audio icon next to the line I was writing at the time and hear what my teacher was saying. However, now when I click on that icon it starts playing past audio. I tried exporting the audio and it worked but only with 2 hours and the part I need didnt transfer and is definitely longer than two hours. Is there a time limit to how much you can record? Is there any way to export or listen to the most recent audio?? Please comment if you know anything about this or can help me!! Thank you so much!!