Hi,
If the icon is not green, it means that one or more services are not started.
A tool integrated in Wampserver allows you to see it:
Right-Click -> Tools -> Check state of services.
On the other hand, if you don't use MariaDB, it is better to disable it, there also by the parameters integrated in Wampserver:
Right-Click -> Wamp settings -> Allow MariaDB to uncheck it
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