Self-signed or locally issued certificates have an expiration date. If your development server has been running for a long time, or you last set it up years ago, the certificate may have expired, breaking the "verified" status. Simply generate a new certificate to resolve this.
: Run mkcert localhost to create localhost.pem and localhost-key.pem .
Getting Chrome to accept a self-signed localhost certificate [closed] 28 Sept 2011 —