1st understand what that lights mean to you!!!
https://www.amazon.com/gp/help/customer/display.html?nodeId=201601790Continue Blue light spinning means Alexa is started-up & busy in processing your request.
Try open the Amazon Alexa App on your connected system & uninstall it, then again add Echo dot again.
But if you're getting this again n again then Please reboot your Alexa or reset your Echo dot:
Press & hold Echo's Action button for 15-25 seconds, then again start the Setup Echo Dot procedure from initial stage.
Try open the Amazon Alexa App on your connected system & uninstall it, then again add Echo dot again.