I have LR6 in Creative Cloud paid monthly. All four panels, top bottom left and right keep disappearing. Clicking VIEW then LOUPE OVERLAY then show sometimes makes the panels re-appear but if they don't the only way to get the panels back is to re-boot LR. Has anyone suffered from this problem and is there a solution please.
This is a known bug. You can try updating to Lightroom 6.10 (although there are reports that the problem hasn't been completely fixed), or reverting back to Lightroom 6.7.
As a minor point of information, you do not have LR 6 in the Creative Cloud, there is no such thing. LR 6 does not use the Creative Cloud, and if you have the Creative Cloud, you don't have LR 6, you have some version of LR CC 2015.X