zero said:

HI  i just started resourcing in home kingdom and after choosing number of troops and clicking on send it said my 1day 12 hours sheild would be invalid to attack target...i took no notice and sent troops .. then went to global map view and it still shows sheild but when i enter town no sheild is on in list so i had to put another 24hr sheild on.... please look at this bug and sort it quickly. 

name ....zero

kingdom 781

Dear Zero,

We understand how important this issue is.

Please provide us with the following information so our specialists could resolve your issue as soon as possible:

1. Specify the date and approximate time when you activated the Peace Treaty item.
2. Provide us with the screenshot of the Battle report of the first attack on your Town. Please note that the date and time of the attack should be clearly visible on the screenshot.

We process each request individually and will start investigation as soon as we receive the requested information.

We are waiting for your reply. Thank you in advance.

This sounds like a delay problem, if you see something is free to go to, and either you take too long to complete the operation, or its game lag, and another player has already landed  on the place that you wanted to go to, the game sees it as an attack.

It has happened to me - more than once.   The first time I also ignored the "warning", but nowadays I just sigh and find another target.   Don't blame yourself, it is not you, it is Plarium.