It's almost impossible to get a smartphone at a lower price than the Redmi 9AT. Fans of long battery life in particular will get their money's worth with the Xiaomi phone. Our review of the Redmi 9A clone will reveal whether the Redmi smartphone is worth buying.
https://www.notebookcheck.net/Xiaomi-Redmi-9AT-smartphone-review-Is-the-99-Euro-smartphone-better-than-the-original.531803.0.html
It might be an ok phone, if you are lucky to get one without flaws!
My Redmi 9AT was made with a disfuncional screen but good battery. After 2 months they changed the screen, it came back whit new screen problems and a bad battery.
I guess you get what you pay for.