iPhone 90% charging limit exceeded

Probably normal. The limit is not a hard cap but rather a target. Your iPhone may charge more than that depending on what it calculates as the most appropriate level based on your usage and charging patterns and it may change from time to time. See:

About Charge Limit and Optimized Battery Charging on iPhone - Apple Support

Regards.

When i set my iPhone15Pro to 80% sometimes it will just charge to 100% then it will revert to my setting of 80%, i feel this is how Apple has designed their charging system.

I just got tired of the 80% and now i just set it to 100%.