Had Lightroom CC subscription on old computer which went Un serviceable so had to purchase a new computer - cancel LRCC subscription and purchase LR6 on disc - installed on 29/9 - used LR OK until Saturday 24 October when LR screen said I needed to purchase a membership to access Develop window. Could not gain acccess to my purcased and installed LR6 = Help Info please Thanks Alfr
I did checked your Account details and Lightroom should run fine on your Computer.
Please refer Solution 2 mentioned here Lightroom doesn't launch or closes automatically after splash screen
Let us know if that helps