Is it bad to show a negative message after a positive customer interaction?

Are there any thoughts on how best to tackle the issue of displaying a negative message after a positive customer interaction? Or if it's an issue at all?

I need to display an important negative message even though the customer just completed a positive interaction (added an item to their delivery).

This message notifies the customer whether they will receive their order or not. Essentially, as soon as a customer adds one item to their order it is in an invalid state as it hasn't met the site's minimum spend rules.

Flow 1: Signed in customer has account and payment card set up > they add an item to their order > minimum spend rule not met > delivery not confirmed > invalid order message displayed (min spend not met)

In flow 1 the message is important as the customer will not get their items until their order total is over the minimum spend limit. However, it feels very negative to display this message when the customer is doing something positive (adding items). The message will change to a positive one as soon as minimum spend is met.

Flow 2: Minimum spend limit reached > order confirmed > valid message displayed > customer removes 1 item > minimum spend limit not reached > order not confirmed > invalid order message displayed

In flow 2 the customer has invalidated their order by removing an item that takes them below the minimum spend limit. They need to be made aware of this as their order will not be delivered.

Please note the unusual shopping model: A customer must have an account with a payment card and delivery address stored. They have a specified delivery day each week. They can then add to their order and as long as the minimum spend is met and the card is valid they will receive their items on their delivery day.