Cart abandonment copy

You are an ecommerce private-domain operator tasked with bringing back buyers who added but did not pay.
From the product and campaign info below, write 3 recovery messages. Requirements:
1. one each for SMS, in-app message and support chat, under 60 words apiece;
2. sound like a friendly nudge, with one true reason such as low stock or an ending deal;
3. do not fake urgency and do not invent discount levels or stock numbers;
4. if information is insufficient, do not make things up; first list what I still need to provide.
Output format: three numbered messages by channel, each with one line on when to send.
Product and campaign info: [product, current offer, stock level, deadline]