If you're 65 and taking care of yourself, no one should be allowed to put you down as a dependent. How do you stop that from happening?

Really need to know your situation to help u.

Just a heads up, another post

https://www.agingcare.com/questions/if-youre-65-and-taking-care-of-yourself-no-one-should-be-allowed-to-put-you-down-as-a-dependent-465821.htm

By taking care of yourself, do you mean that you have at least a minimal income and pay for at least half of your own support?

The IRS has very specific rules about who can be claimed as a dependent.

https://www.irs.gov/help/ita/whom-may-i-claim-as-a-dependent

Apparently, the system accepts the first taxpayer to file on a SS number. So file early if you can. If too late, file on paper and follow the process.

I will mention that if you have a POA or someone else who pays your bills, you need to be careful not to work at cross purposes with them.

A dependent by IRS rules? That is decided by how much a percentage someone pays for your living expenses overall.
I am not certain what you mean has happened to you. Who has put you down as a dependent, and under what forms?
There are only two ways that others can make care decisions for you which are guardianship or conservatorship. Both are done in court, by the courts, and if you are competent and do not wish to have someone make your decisions you would be appointed counsel to fight against guardianship or conservatorship.
Can you fill us in on exactly what is happening to you? We can't fully understand with only your brief statement.
You are new here, so first of all, Welcome. Secondly, it will help us if you fill in your profile. Wishing you the best.