Hi,

If you are using Calculated shipping options, the first thing to check is the Postal services offered for Domestic and International are allowable for the weights you have used.

Be sure you do not have 2 of the same choices on Domestic and International. e.g. 2 First class choices or 2 Parcel choices, etc.

Next be sure you have selected the countries to which you will ship on all offered services. \

eBay is not allowing Airmail Letter Post for a great deal of packages. So if you have offered AirMail Letter Post as an option, you probably will need to select another service in its place.

Try that and see if it works better.

Judy/blue