Coal Deposits??

I have sent my geologist out several times to find coal deposits, each time he returns I get the message " coal deposit not found as you already have too many". I have no coal deposits and have even tried deleting my coking plants but this makes no difference, any suggestions or has any one else had this problem?

yes, refresh your browser.. I have this many times a day for marble deposits then they suddenly appear after a refresh. Only other suggestion is (and forgive me for this), have you cleared enough of your island to find further deposits? You need to have a working storehouse in each sector to be able to claim the sector and find more deposits..

Yes I do have a storehouse in each sector, I have also refreshed, this only happens with coal, iron, copper, marble & stone are not affected.

Just a quick question but have u claimed sectors 6 and 7?

Here's a Resource Map, just in case.

I have also got this issue, i am level 50, and on a daily basis i can send up to 6 explorers out to find 1 or 2 deposits. I currently clear all caches and refresh up to 8 times a day, but nothing fixes.
This has only started happening to me since removal of the last event. It happens with marble mainly, but can happen to iron and copper on occasions.