Change the color of Instagram messages

I have 4 accounts: one where all the messages are black, another where they are gray, one where they are gradient blue-purple, and a last one where they are sky blue. I haven't done anything particular, but I would like to change them all to a gradient!

Same here, I have the updates and my second account has the colors, but my main account doesn't.

I have two accounts and one of them has messages that have turned blue/purple while the other one hasn't.

Hi ... it's really easy
You go to messages
You tap the message with a friend and then you click on the i at the top, then you click on theme and there you go, you'll have plenty of colors and even the original one.

He set the dark mode on his phone
-Settings
-Display & Brightness
-Dark

I can't change myself, but it changed by itself on a second account without me doing anything. So now the messages at the bottom of my screen are blue and those at the top of my screen are purple. So if you scroll up in the conversation, it changes the purple ones to blue, and the ones that come in are purple. (Purple gradient like the Instagram logo)

Could someone tell me how to remove them and go back to how it was before? I hate this.

Hi, it's strange, I had this before, but since I deleted Instagram and reinstalled it, it doesn't work anymore. I can tell you that it doesn't just add colors to the messages; you can react to messages with any emoji, it all depends on the device you're on and the account you're logged into. I think it has something to do with the amount of time spent on Instagram with your account?? And it has nothing to do with an update; it will ask you to update the conversations when you open Instagram. I have doubts if all this is related to the Messenger app from Facebook.