Hi,
Many thanks for your question. My name is Tim and I’ll try my best to resolve your issue.
I’m just wondering what fonts you are using? Are they standard Microsoft ones or different?
There is a link below which is similar circumstances to you where it was recommended to do the following:-
Can you try embedding the fonts into the file when saved as detailed below:-
1)Choose File>Save As>Browse.
2)In the Save dialog, click on Tools>Save Options and check the Embed fonts in the file.
3)Choose the Embed all characters option, then click on the OK button.
https://answers.microsoft.com/en-us/msoffice/forum/all/formatting-issues-with-powerpoint-occuring-when/642d5696-7fff-4c7e-a0db-fe07a4042259
Give back to the community. Help the next person who has this issue by indicating of this reply solved your problem. Please click Yes or No below.
If you thought my advice was helpful I’d really appreciate you pressing yes on my reply.
Look forward to hearing from you.
Many thanks
Tim