Have you tried connecting to another port on the switch?
If it works, it is probably the current port that is defective, otherwise try changing the cable as already stated.
In the worst case scenario, open a support case.
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
Please, if this post was useful, leave your kudos and mark it as solved.