Long-press the address - choose "forget". (And if you printed to your neighbor's printer, I'd change the password and channel on the router - your neighbor is probably using your router. [It's not very common, but if your ISP finds out - and they can - they might disconnect you, sue you (and your neighbor), ask the law to prosecute you ... it's called "theft of service" (which your neighbor is guilty of, but you're complicit in). When you pay for internet service, it's for a single premises, and a single family unit, and you can't legally share it.])