LB asking for activation Key

Purchased from OMTech with my 80w, Installed LB on my laptop with Win10 and activated 6 weeks ago. Ran LB with no issues for last 6 weeks. Then Win10 did an automatic update last night, when I started LB today – it said trial period had ended and to enter the activation key. Thinking this was strange - I did a copy and past of the activation key that had successfully worked 6 weeks earlier.
But, LB reports invalid activation key. I have no idea what to do next – I copied and pasted the key sent by OMTech 6 weeks ago - that has worked to register LB 6 weeks ago.