The product suddenly could not be searched using the core keywords under All departments. It had previously been at the top of the homepage, but now the product can only be seen by searching and selecting a specific category. The ads can run normally.

Answer:

Based on what you said, let me tell you my thoughts.
There are several reasons why a product suddenly cannot be found on the front desk: it is marked as an adult, the link is downgraded, competition from peers increases, the front desk delivery address is wrong, the category node is suddenly changed, it is blocked due to illegal review or incorrect information, and it is out of stock.

You said the ad runs normally, which means the link itself is fine, so:
1. First, check the sales trends of your peers on the first three pages to see if there is an upward trend or if some small sellers have rushed to the front and relegated you to page 7 or later.
2. Check whether you have done anything recently and whether there is any black technology that has caused the link to be devalued.
3. If the ad runs normally, download the data to see if it is normal.
4. Check to see if there are any changes to your category nodes.
 
Suggestions: 1. Increase your advertising budget to expand your traffic channels and see if the incoming traffic is normal.
2. Considering the deterioration of link performance, set a small discount first to increase the conversion rate, and observe for 3 days to see if sales and keywords recover.
3. Open a case and ask customer service. It is always better to ask more questions. If one customer service representative doesn’t have an answer, ask a few more. There will always be customer service representatives who understand. Ask them what the problem with your link is and ask them to use their resources to check. There will always be some results.
4. You can do off-site sales or flash sales to stimulate sales weight first. The ranking of keywords is also closely related to sales.