My Lightroom is now saying I my trial has come to an end and is directing me to now purchase, however I have bought it from a store and have been using it for months. How do I access Lightroom without having to purchase again?

This might be the same issue from this thread: https://forums.adobe.com/message/10899684#10899684

And don't forget the basics: make sure you log in with the correct email address!

which version?

if perpetually licensed, reenter your serial number (help>activate or sign-in).

if a subscription, check your account to verify your subscription is what you expect and to verify your adobe id (used in the next step), https://accounts.adobe.com/

if your account shows

a. your subscription is active,

1.  sign out and then back in to your cc desktop application using the same adobe id above to verify your subscription:  http://helpx.adobe.com/creative-cloud/kb/sign-in-out-creative-cloud-desktop-app.html

2.  if that fails, https://helpx.adobe.com/manage-account/kb/stop-creative-cloud-trial-mode-after-purchase.html

3.  if that fails, https://helpx.adobe.com/creative-cloud/kb/cc-reverts-to-trial.html

4.  if that fails, using a browser that allows popups and cookies,  contact adobe support during pst business hours by clicking here and, when available, click 'chat', http://helpx.adobe.com/x-productkb/global/service-ccm.html

if your account shows

b. you have no subscription and you're paying for one

1. using a browser that allows popups and cookies,  contact adobe support during pst business hours by clicking here and, when available, click 'chat', http://helpx.adobe.com/x-productkb/global/service-ccm.html

[moved from Installing, Updating, & Subscribing to Acrobat to Adobe Creative Cloud]