I have had two new units that had some bubbling.
Both got better on their own. It seems that the roofing material will shrink some as it ages, and the bubbles disapear then.... In fact I think some bubbles might be beneficial so that when the material shrinks, it doesn't pull away from where it is supposed to be.
Both of my TTs with the bubbles were bubble free in a year or so, and trouble free for at least 10 years.
Now I suppose the bubbles can be large enough to cause trouble... Some pics would help.