A sad fact of life that this sort of blemish occurs. Getting a fine mirror like finish and then trying to get some "paint"or plating to stick is almost asking for miracles. So many factors mitigate against success that it is almost suicidal financially for an instrument manufacturer to

"guarantee" lacquer or silver plate finishes. When I worked for Schilke over 40 years ago he could not "guarantee" the best possible Anderson silver plate finishes, though we did our best possible to ensure a fine finished product.
At that era you were lucky if your best new Mirafone, Alexander or Meinl Weston would hold its lacquer much more than a year and blemishes like in the photo were common on brand new instruments.
The extra time, effort and expense required for manufacturers to completely avoid such "defects" for even a 2 year warranty period would add a LOT to the price of a new tuba.
The advice offered above is probably about as good as it gets.