This sort of experience is becoming quite common for numerous government online applications. Checking a web page URL (address) to verify its source is prudent.
Most countries use a reserved domain or sub-domain for official government sites. The US, for example use .gov. Any web site URL ending in .gov is a US government website. Canada uses .gc.ca and .canada.ca. The UK uses .gov.uk. Australia, .gov.au. New Zealand, .govt.nz.