According to the datasheet, flashing white indicate that a firmware upgrade is in progress.
My Status LED is blinking WHITE
A blinking WHITE Status LED indicates that the device is in contact with the Dashboard Cloud servers and is performing a firmware update. This can sometimes take 20-45 minutes or more to complete depending on hardware and other factors.
MS225 Overview and Specifications - Cisco Meraki
Does the dashboard indicate that you have any currently running firmware upgrades?
Did you notice the issue prior to running the firmware upgrade or only afterwards?
Which firmware version are you running?
You could try rolling back the upgrade and pushing it again to see if the changes it.
Managing Firmware Upgrades - Cisco Meraki