Issue with rendering output resolution

[Valentina]

Hi, I have the Creative version of Terragen 4 and a maximum resolution output of 5K. Since yesterday, in some scenes, if I render with more then 1920/1080 I receive this message: ''the creative edition does not allow you to render sequence images larger than 1920 x 1080 pixels''.
That's weird, for I've been rendering for the last year regularly and never had this message. Besides, I'm not rendering sequences, or animations. Just stills. What setting may I have changed? If I open a bare new scene I can render to 5k. I can't see differences between render settings. Frustrating I'm not figuring it out, but I hope you can help.
thank you
Valentina

[Matt]

This happens if the current frame is something other than 1. If you change it back to 1 it should fix it. (It's on the timeline at the bottom of the main window.)

[Valentina]

Thank you! 
Sorry, I didn't think about checking the current frame.