Any modern AI model can be provided "tools" that it can use to perform various tasks or retrieve various information. The current date and time is easy to do. I can't say why the author and/or ChatGPT seems to have trouble but you can easily set up a tool to return the current date and time, instruct the AI "this will return the current date and time" and then if the user asks for it the AI will automatically leverage the tool. It's possible ChatGPT just has a lot of tools at its disposal and is getting confused about which one it should use (for example, searching online for the current date time) or perhaps OpenAI wants ChatGPT to use a less specific online search tool which can also return the current date/time when asked but sometimes ChatGPT doesn't quite search for the right thing. As someone who has leveraged AI you can provide specific tools but I expect OpenAI wants to provide far more scope to tool functionality in ChatGPT, so may provide more general tools like web search, which may cause problems.