Fortress bug

[Kakta]

Hi, I have an issue with fortress. It says that it needs 63k stone to upgrade. ( i am new) but maximum capacity that can be stored is only 35k. How on earth can I upgrade my fortress? I mean it might be mistake with some quest or something. Because I upgraded fortress and if I recall it well there was a reward to automatically upgrade to level 3. Current level is actually 3 but the price to upgrade it is like to level 5. My acc name is KaktaLt v6 177. Thanks

[Madzoism]

It's not a bug. You've reached the fortress storage capacity but you can still stash resources there (transport from other provinces, from looting or from the market) Once you reach the maximum that province will no longer produce that resource, in your case stone.