Instructions: In this task, you're given reviews from Amazon's products. Your task is to generate the Summary of the review.
Input: Well, I initially left a very favorable review of this product after trying it for a couple of weeks. However, 2 days after the return. Expired, the left earbud failed to function at all. It does no good for me to have one earbud that is workable and the other non-functional. Doesn't really help at the gym. Perhaps it's just a bad batch. But I have to say, I won't be purchasing the same brand again.
Output:
Had to change my review of this product. Not so great.