I have a Verizon iPhone 6s (not jailbroken). At approximately 1:00 a.m. on September 21, 2018, several SMS text messages (green) were sent to many of my contacts. The messages were just a mess of different characters and emojis and also a link via Google and Yahoo to different sites (see attached screenshot). I was asleep at 1:00 a.m. and my phone was on my desk plugged into the charger. No one else has access to my phone or knows my pass code. Anyone else encounter this? Should I be worried? Are there any measures that can be taken to avoid this in the future? Thank you in advance for any assistance!