Tealium is taking almost 10-15 minutes to load a profile and equivalent time to publish the profile.
I see many synchronous Ajax calls in network tab triggering to https://my.tealiumiq.com/urest/ping?utk=2180b3e10e2e4015cb0304dcb1cf54b0bb3d8c1b3825017357
Could you kindly suggest a solution?
The ping requests won't be what is causing your issue.
I would raise a request with the Customer Success Engineer (the Support team) with the account / profile that you are loading.
You could also use this tutorial to generate a HAR file so we can analyzer what you are seeing.
The slowness is most likely this is due to the size of your profile, there are ways this can be addressed, again this can be discussed once a ticket has been raised.