What is it called when people decide an issue for you and you have no say in the matter?

Solution 1:

One option could be:

unilaterally

adverb
UK ​ /ˌjuː.nɪˈlæt.ər.əl.i/ US ​ /ˌjuː.nəˈlæt̬.ɚ.əl.i/
​in a way that involves doing or deciding something without first asking or agreeing with another person, group, or country:

  • The region is seeking to unilaterally declare independence.
  • The rebels continue to attack from their side of the unilaterally determined border.

-- Cambridge Dictionary