Help! Lightroom Payment on Free version?

Hi,

I have fairly no experience with adobe apps on the iPad, but I know how useful is Lightroom on desktop. So about 2 years ago I have downloaded the Lightroom app off of appstore and used it just for a bit back then. Nothing was charged on my account for Lightroom or Adobe creative cloud. Recently, couple months ago, I've started using it again regularly and everything went as smooth as before. However, now I cannot use the app anymore and everytime I want to do the most basic edits I am restricted by a pop-up screen reminding me to renew my subscription and get the newest features! I have never had a subscription! Now, I understand the app offers certain special festures for a monthly payment, but I've never used those nor do I want them. If there was an update that stopped or limited the free access, there was no notice for it.

My questions would be, is there some sort of update that caused the free period to end? Or is it an error? If I want to start using Lightroom ever again I have to sign up for the subscription? Is that also including the special features?
Thank you!