Amanda Bynes I Didn't Post Nude Photo ... Account Is An Impostor!!!

Amanda Bynes is denying posting an alleged nude photo of her in a bathtub ... she says she's not the one in the pic, nor is she the person running the Twitter account that put it up.

Amanda tells TMZ she never takes nude photographs like the one circulating the Internet purporting to be her, and she's never had a connection to the Twitter page where it first popped up.

Amanda’s attorney, Tamar Arminak, tells TMZ … Amanda is NOT the naked woman in the photograph posted this week on Twitter, and AB's legal team has been trying for years to get Twitter to get the account in question taken down, to no avail.

Her attorney claims Twitter's refused repeated requests to deactivate the account, which uses the handle @PersianLa27, and says Twitter's refusal rests on their position the account is a celebrity parody page.

Amanda's lawyers tell us they even tried to use her former conservatorship as a catalyst for Twitter taking down the attack ... but the bird app didn't budge.

And, get this ... Amanda's attorney tells us, "There's nothing funny about what she was going through mental health-wise and the fact Twitter thought it was appropriate to keep a parody account mocking what she was going through is disgusting."

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