If you get this error after deploying your application on Vercel, trying to retrieve the data but it turns out error 504(Default timeout). Do this:

• First check the deployment regions, try to make them be near each other.(the region of where your database is hosted from and website region on vercel)
• After that change the ip address to 0.0.0.0/0 for easy access anywhere.

For me I was using #MONGODB, #nextjsAPI, #Vercel for deployment when facing that error. I dont't know if it can work for others