When attempting to create a listing, you may run into this error.
It means you've reached the SKU limit for your Subscription Plan, and may need to upgrade.
Once you've decided on a plan that suits your needs, just reach out to us via phone or email and we can get you switched over so you can start listing again.
However, if you are not ready to take the next step, you could delete some of your current listings to make room for the new ones. You can delete listings manually in listing mirror or using a bulk edit template.
If you need any assistance or advice, feel free to reach out to support.