I've tried to recreate your problem your experiencing however I'm not getting an error..

Can you confirm the steps your taking to get the error..

Its not easy to recall all the steps i have done prior to the first time i got the error.

I have saved a lot of contacts in the past but have not chosen one of the icons while saving them.

I suspect that could have something to do with this problem.

Somehow those old saved contacts are not visible in my contact list anymore, they seem to be replaced by other bases i raided or reconned lately.

Because i cant see those old contacts anymore so i cant delete them.

Flea Ridden Basterd said:

Its not easy to recall all the steps i have done prior to the first time i got the error.

I have saved a lot of contacts in the past but have not chosen one of the icons while saving them.

I suspect that could have something to do with this problem.

Somehow those old saved contacts are not visible in my contact list anymore, they seem to be replaced by other bases i raided or reconned lately.

Because i cant see those old contacts anymore so i cant delete them.

Thank you for the information and I think I basically able to recreate your problem.   So it appears not that you would not have saved any contacts without an icon, however the default icon is "info" or the orangish box with the "i".  However this is the same icon they use for contacts you haven't added that you've send resources or such for allies and raids on enemies.

I was able to click through my contacts after adding a few.  On the left side just clicking the icon, it either given you one option "save" which means that it is a system added contact... or "save" and "delete"  which means it was one saved by player... Let me know if this helps!

i know what you mean and have tried it before.

i could find 1 old contact that way and deleted it.

I also wandered around on the map and found 2 more who i have deleted.

I had expected to be able to make more contacts now but i still cant make more then 5

I could see a good suggestion to be made in the suggestions forum, about maybe a way to clear all contacts!  

However at this time I do not see a function for that, and i understand it can be frustrating.  On the community forum we have no access to your account.  I am unsure if the support team is able to clear the contacts from your account, however you are free to contact them by opening a support ticket at    https://plarium-mobile-support.zendesk.com/hc/en-us/requests/new