In the admin module, you have the option to modify quota limits.
If you scroll down, you will see a green button called "Change Quota Limits".
Click on this button and modify the relevant quota limits then save.
You should make the same changes using Sawtooth Software's authoring tool. If you need to upload your survey again, you will want it to incorporate the changes and not the old limits.
I believe this warning will be displayed when you save your modified quota limits in the admin module.