Ever since updating to IOS 18, my messages are disappearing

Ever since I updated my Iphone 15 to IOS 18. I have had a problem with one of my contacts messages. I have all the texts up to the day I updated (September 21st) but between then and now every time one of us texts a text from a previous day gets disappeared. So for instance after the 21st the next text I have is from September 29th and is an address. But if I was to send a text now then that message would disappear. I am using the term disappear because if I go out of the conversation and use the messages search bar I can still find the messages from those 8 days but upon pressing on them it just shoots me to the last text on the 21st. This is only happening with this contact, and am wondering why. The only difference between them and my other contacts is that i have an email address in her contact card since she sometimes texts me from her mac. But not all the texts from the 21st till now have been through the mac. Also all the photos, links and videos sent in that time span are still able to be seen if i click on her icon in the conversation. Has anyone else experienced this, and if so were you able to fix this.