Data usage way higher with ios18

I have an iPhone 15 Pro Max and recently updated to ios18. I have used all my highspeed data very quickly and today I added 2GB more and it was gone in less than 5 minutes. Carrier said that the data usage number they have are accurate. Is anyone else having this problem? I have never maxed out my high speed data beore and my routine/usage habits have not changed. Any suggestions on what to do? Thank you!