I had same question but for a different reason is it possible and how to change an old fingerprint for a new one. And as I can see that's not a problem - just use new FP and it will be updated in the profile.
What about your concern about the red flag etc, I I believe that you are overthinking. Bunch of people update their browser regularly and if it would be a reason to block anybody account it would be a total mess. But if you are worry, just change a old FP to a new one, that's it don't do some rare activity, that could be considered suspisious same time like make a $10k payment from your account etc)). Just do it next time you login.
But changing user agent manually can be an unnecessary костыли in this case
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