Can not open files that are shared with me through Sharepoint

Hi @Marina Signorelli 

Thank you for posting your question in the Microsoft Q&A forum. 
I'm sorry you're experiencing this issue. It must be incredibly frustrating to complete the approval process and still find yourself unable to access the file. 
SharePoint may take time to propagate permissions. You may try:  
-Clearing browser cache or using different browsers.  
-Opening the file in a incognito window. 
-If you're using Safari, its privacy settings may block cookies or scripts required by SharePoint. Try accessing the file using Microsoft Edge for Mac or the OneDrive app instead. 

Additionally, please confirm whether you're an internal or external user.  
-If the file was shared using the setting People in your organization, only members of that organization will be able to access it.  
-If you're external, the file owner will need to update the sharing settings to People you choose and enter your email address directly. 

If the issue persists, you can ask the file owner to: 
-Remove your access entirely and then re-share the file with you.  
-Use the Manage Access feature to explicitly grant permission can sometimes resolve lingering permission glitches.  
-Double-check your access under Manage Access. 

I hope this information is helpful. 
If you have further concerns, please feel free to reach me out.

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