There has been much discussion over the past few years about the problems inherent when messaging between iOS and Android. Apple’s iMessage rules the day for iPhone users, while the cross-platform RCS powers Android. Apple refuses to play along with RCS, so texting between the two platforms is a less-than-ideal experience for all.

However, today, things are more messed up than usual (h/t 9to5Mac). There are multiple Reddit threads filled with folks talking about how iPhone and Android texting isn’t working properly. It’s causing mayhem for people’s chats and could also result in some texts simply not going through.

Although it’s not really clear what’s exactly happening, it looks like a “+” symbol is getting added to Android phone numbers somewhere along the chain. The steps look like this:

• An Android user sends a text to an iPhone user
• That text gets converted to SMS, as usual
• Either the carrier network or iOS erroneously appends a “+” symbol to the Android user’s phone number
• The “+” symbol makes the first number seem like a country code rather than an area code
• The iPhone thinks the number is an invalid number and either rejects it or creates a new chat

As far as we can tell, this problem started today. It also appears to be affecting people when AT&T is involved, although it’s not clear if that means it’s an AT&T problem. Regardless, if you notice this phenomenon happening in your own chats, know that you’re not alone! Hopefully, we’ll get word soon on what’s happening and what’s being done to fix this issue.