i download .NET SDK Project from paypal and run it, here i see that they give a option to create Billing Plan which is using for creating product and subsription plan.
take a look to this article: https://developer.paypal.com/docs/subscriptions/
With this project i create a new Plan succesfully
with this id: P-1FM52925BU386645MF32EE4A
Then i create new simple html page and add subscribe button with this code which is attached to the subscription plan:
<script src="https://www.paypal.com/sdk/js?client-id=[sandbox-client-id]&vault=true">
</script>
<div id="paypal-button-container">
</div>
<script>
paypal.Buttons({
createSubscription: function (data, actions) {
return actions.subscription.create({
'plan_id': 'P-1FM52925BU386645MF32EE4A'
});
},
onApprove: function (data, actions) {
alert('You have successfully created subscription ' + data.subscriptionID);
},
onError: function (err) {
// Show an error page here, when an error occurs
alert('Here is error: ' + err);
},
onCancel: function (data) {
// Show a cancel page, or return to cart
}
}).render('#paypal-button-container');
</script>
Then i can see the subscribe button and if i click i recive an error like in the image below: 
It seems like he cannot find the plan, but if use SDK .NET project to get all plans i can see that the plan exist. Also i take a look in my developer account in API calls section and i can see this
There are some warning probably becasue of the error i see after clicking subscribe button but without any explanation. At this image we can see that the billing plan is created succesfully.
Can you please help me what is wrong?
