Enemy armies massing/stuck on campagin map.... know issue?

During my High Elf campaign Naggarond kept being as strong as me on the balance of power bar, even though I kept expanding in territory and armies and I didn't see any army movement from Naggarond...

Until I stumbled upon 6 or so fully stacked armies stuck in 1 place on the campaign map (explaining where all their power was and why it was so easy for me to take over the whole map).

Is this a known bug?

(tried to upload an image but it didnt work)

Absolutely it's a bug, I think you have no choice just capture their all cities and after one turn all 6 armies and Naggarond get destroyed!

but if you couldn't upload an image the better way is, record your games upload the video on youtube then share the URL here.