It’s by design to force people use iPhones. lol jk. It’s a known issue and it might have to do with settings on his iPhone. Tell him to go to Settings > Messages and somewhere on that page he should be able to select the active number or iCloud account. Make sure to remove the Android’s phone number, and hopefully that should fix it. If not, delete all the numbers and accounts, then try texting his Android number.
@Sky
How long has this been a known issue?
For many years. Try the suggestions I wrote earlier and report back if it worked so others can learn from it.
For many years. Try the suggestions I wrote earlier and report back if it worked so others can learn from it.
It didn’t work.
Just now we’re tryna troubleshoot. I got a cornucopia of diff issues. Apple software is dog 
.
Deleting contact AND messages lets me text the Android. Trying to resave the iPhone number together with the Android breaks it again. Then it fails to deliver on Android.
After doing that a couple times, I COPY PASTE THE ANDROID number and it CHANGES IT TO THE IPHONE NUMBER AND TEXTS IT INSTEAD. Sometimes it changes it to the contact name that I already DELETED and it THINKS IT’S STILL SAVED UNDER THE DELETED NUMBER (after both iOS and Android contacts are deleted).
Another time, it kept spinning wheel on the Android number and ANOTHER time, the number stayed blue even though it was an Android number, and ANOTHER TIME, the send button was greyed out. The steps didn’t help. I still can’t text the Android unless I don’t EVER text the iPhone. If I ever text it or get one from it, it combines the two numbers even though they’re two DIFFERENT NUMBERS, and their Android number is no longer in their iCloud.
@San
A sure way to fix it is by backing up both phones with iCloud/Finder, doing a full factory reset (Settings > General > Transfer/Reset > Erase all contents and settings), skipping all the setup steps, and then testing it WITHOUT restoring any data from iCloud. If it works, restore the data and test it again just in case. The reason why you need to do it on both phones is that you don’t know exactly which one is causing the issue.
@Sky
You think anyone at Apple support would know?
San said:
@Sky
You think anyone at Apple support would know?
They will probably just tell you the same: back it up and factory reset it, but they won’t tell you to test it before restoring the data. That’s important, otherwise, you might restore the corrupted settings causing the issue in the first place.
@San
iMessage has a mind of its own wtf.
Seems like this is something on your friend’s end. They may need to deregister their Android phone number with iMessage if it was ever added to the iCloud account. Link: Deregister iMessage
Is their number still connected to an iCloud account/email that is connected to another Apple device like a Mac or iPad? Could be why.
The solution is pretty simple. Just save them under different contacts.
Nori said:
The solution is pretty simple. Just save them under different contacts.
I tried. iMessage is still grouping them as one contact and ignoring the Android number.
Nori said:
The solution is pretty simple. Just save them under different contacts.
I tried. iMessage is still grouping them as one contact and ignoring the Android number.
That means it’s on your friend’s end. They didn’t remove their Android number from iMessage on their iPhone. Settings > apps > messages > send and receive. If they also have an iPad, check there too.
Nori said:
The solution is pretty simple. Just save them under different contacts.
I tried. iMessage is still grouping them as one contact and ignoring the Android number.
Do they have different names? Try making a new thread with each of the numbers and see if that works.
@Nori
Different names, no names, doesn’t matter. The thread always combines no matter what after multiple attempts of deleting the threads.
Sometimes texting the number individually worked (if I only text it and not the other, so there’s nothing to combine), but now it’s literally changing the Android number INTO the iPhone number before my eyes after I hit send.
@San
Have you tried deleting both contacts, restarting the phone, verifying that they’re both different threads, and then saving their numbers again?
Nori said:
@San
Have you tried deleting both contacts, restarting the phone, verifying that they’re both different threads, and then saving their numbers again?
Yep. Did all of that. The problem just repeats.
@San
I’ve literally been troubleshooting this with my friend for 2 hours now.