iPhone not working but iPad is working with chromecast I have been using my phone to cast to my chromecast for almost a year with no problems but about a month ago my phone stopped seeing that my chromecast was available.  Fortunately I have an older iPad, so in the case where my phone does not work I use my iPad to cast which still works as it always has.  My iPhone and iPad are both on the same WiFi network so if one sees the chromecast, so should the other.  Why does my phone not see my chromecast on the same WiFi network but my iPad does?
What I have tried:

In the beginning I found that if I reset the chromecast that would allow the phone to see it and cast to it, but that does not work anymore. RESET CHROMECAST = NO
I try resetting my iPhone but there is no change. RESET PHONE = NO
In the beginning I found that if I reset the WiFi router that would fix it, but that no longer works. RESET ROUTER = NO
I thought maybe the chromecast was old and breaking so I recently got a new device but that did not have any effect on this problem.  BUY A NEW CHROMECAST = NO

My conclusion:
I may be wrong, but the last thing I can think of is that the phone is broken.
Does anyone have any ideas before I conclude that the phone is just broken?
I'm afraid that I don't have an answer with something as hard so sort as this problem remotely, but I don't believe it is your phone.

I have recently started to have exactly the same issue.
Both my partners iPhone and mine, which we both used regularly to cast to the Chromecast are no longer able to do so, and we are using an older iPad, which does still works.

I had initially come to the same conclusion that my phone must have been the problem, but I can't see that both of our phones, which are different models would have broken at the same time.
I’ll be looking to do all updates in case a recent one has triggered this.
We also have a more recent version of a chromcast (the round version) in another room, and the phones still work fine with that one.