I think this is just a glitch because no human can connect and disconnect a miner in under 5 milliseconds.
It's also not a breach. I have a similar issue on my miners before thinking about someone giving me free hashrate, but it's not.
Do you have stable internet? My case before was due to unstable internet or something on my network that disconnected and connected my miner within a second, which caused extra worker to be added in my dashboard.
three separate mining locations soon to be a few more. that may be why