Text bomb crashed iMessage in 2023. Was my device hacked?

Last Sunday, I received a text from an unknown number and the notification from Apple ID saying something about a password immediately followed. I haven't seen what the text was about, but when I opened iMessages, the app crashed and all my messages disappeared. I had to restart the app. All messages were back, except of the new text bomb that crashed messages. I could only find information about text bombs from 2020. I changed my Apple ID password and 20 minutes later I got a notification that new device was added. It was called just MacBook, but my MacBook is also called like that without a name. I didn't use my MacBook when I got that notification though. It was off, and I didn't find any unknown devices. I removed all devices except of my phone from the apple account. I changed passwords everywhere and created a new Apple ID for my MacBook. I deleted that hacked Apple ID.

Nothing happened the following week, except of today (Sunday again). Around the same time it happened last week I got a text from an unknown US number saying "hi". Never happened to me before. I'm paranoid at this point and plan to change my number and reset the phone. Is there a possibility that my phone got hacked via zero-click malware? Haven't noticed any other suspicious activity like a draining battery or suspicious screen time.