You are able to report the issue in the link provided if you feel this as necessary, however if nothing else, you will have to possibly wait a bit of time to see if the connection re-establishes, as this could very much be an issue on Jagex's end.
That's an issue caused by the connection from some ISP to the RuneScape Servers. There really isn't anything you can do to fix it. You could try using a VPN on your computer which might let you login. Other than that, the only thing you can do is wait it out and check in the next few days if the error has gone away.
Could be someone brute force logging in to your account. They only need to fail password wrong 5 times to lock it out... it's why many players want to hide their log in name (or email if you made an account after 2011).
It happened to Zezima for so long and Jagex couldn't fix it for him.Omnia CC
Had the same problem. Played with 4 accounts at the same time. Thought I was banned for no reason because may be failed bot detection or something. Paniced because I thought I could do nothing, was banned for like 2 hours and did not know if there is a feature for me, since all accounts were banned. Paid like 380€ recently for membership for multiple accounts and paniced that I have lost it all, when it was just a technical issue. Was going to give my 4th account membership but not sure if that's worth doing with those log in problems.