We recently hired a consultant to help develop some new features for our website. He did a fantastic job, but we ran into a little issue. One of the features he built out for us only half worked. Incorrect information was showing in the wrong spot (date showing under the time slot) and there was a missing button field... so essentially, we couldn't even use the feature he built out.
Due to a time constraint and the fact the feature wasn't being used at the time, the issue wasn't caught at launch. However, a few weeks later when we started using it we noticed the issue. I had contacted him explaining the situation and specifically asked if this will be billable or something that he would just fix for us (I have to approve all expenses by my boss first). He did not respond, but went ahead and did the work. I assumed (stupidly) that since he just went ahead and did the work, he was fixing it for free because he didn't deliver what we had originally asked for.
Flash forward, I received a bill for the hours he used to fix this issue and my boss is going ballistic, refusing to pay to fix something that turned out to be broken. I can understand that maybe the time lapse was out of range for fixes, but at the same time I specifically asked about hours before he started work. Is this something we need to pay for and how would you suggest I approach the situation? I understand his time was spent on the project, but the project was never technically approved. We enjoy working with him and don't want to ruin the relationship, as we have a second large project coming up soon.