Yes, four days before I too tried for screen mirroring with Amazon Fire TV Stick, it's not possible with Nokia 7 plus, but my brother phone is Oppo real me 1, it is having the screen mirroring feature, Non-sense from Nokia a 26000 vs 10000 rs. 10000 is better.
PLEASE ENABLE THIS SCREEN MIRRORING FEATURE IN NOKIA 7 PLUS IN FUTURE UPDATES
Dream on, Nokia does not care about support for miracast. There are request since the first HMD Device (Nokia 8) but they even dont respond in the Forum, not on Twitter and so on.
Learn for the future, go for a company which fits your needs (xiaomi, One, Motorola and so on)...
I'm using Chromecast Ultra.
this is great...but i think a bit aside of the thread. We talk About miracast/widi...not Chromecast extra purchase stuff