New Windows computers (whether they be desktop or laptops) are normally sold without any version of Microsoft Office on them. (There was a period when Microsoft provided a 'Starter' version of Microsoft Office programs with some versions of Windows but, to the best of my knowledge, that no longer happens).
So you have to pay to get Microsoft Office. To muddy the waters further though, Microsoft have switched their business model so that, instead of actually buying Microsoft Office as a one-off purchase, users are now encouraged to subscribe to 'Microsoft Office 365' for £59.99 per year (or £5.99 per month) if they're only using it on one computer.
From what you've written, I strongly suspect that you accepted a free trial of Microsoft Office 365, with the trial period now having expired. (That's why you're seeing 'unable to verify subscription').
You can actually still buy Microsoft Office as a one-off purchase (even though Microsoft don't actually go out of their way to promote it) but it will cost you £119.99
http://www.microsoftstore.com/store/msuk/en_GB/cat/Office/categoryID.64542500?tduid=%2892670e0614c4db88cc61423b7ced2649%29%28266696%29%281228294%29%281-9006-__-K2pqOXRscmxmdMOVbGZiajlldzEzNV0=%29%28%29
The solution, of course, is to ditch Microsoft Office altogether and switch to a compatible freebie. There are three main contenders, all of which are excellent products. LibreOffice and Kingsoft Office Free are both well worth considering but by far the most popular alternative to Microsoft Office is the wonderful OpenOffice:
https://www.openoffice.org/
If you download and install OpenOffice you'll be able to do everything that you can with Microsoft Office and (possibly unless you want to open and edit incredibly complex files that someone has created with Microsoft Office) you'll find it fully compatible with all Microsoft Office formats.
A useful hint though:
By default, OpenOffice saves files into its own format, rather than using a Microsoft format. You can change that by remembering to use 'Save As' (and then choosing a Microsoft format), instead of 'Save', whenever you save a document but it's far better to change the default setting so that OpenOffice
automatically uses Microsoft formats (so that people whom you might email files to can open them with Microsoft Word). The instructions are under 'Default file formats' here:
https://wiki.openoffice.org/wiki/Documentation/OOoAuthors_User_Manual/Getting_Started/File_formats