Messages conversations loading slow on my iPhone 15 Pro Max

Over the last 24 hours, when I go to open a Messages conversation, it takes 3 seconds to load the conversation. Every conversation takes 3 seconds to load. I have an iPhone 15 Pro Max and am running 18.3.2. Nothing else on my phone is loading slowly. I've tried rebooting the phone a couple of times, but that hasn't made a difference. Any suggestions on what might be causing this? Has anyone else experienced this? Thanks. 

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