We are sorry to hear that! We can exclude that there is a problem with the seeds, because we have all our seeds tested by independent institutes for germination and viability before production and are also subject to constant state control. Furthermore, we use our own test areas for growing and sowing.
If the plants do not bear fruits, it is certainly because there was a problem with pollination of flowers. This can happen when there's no chance of pollination by beneficial insects (perhaps due to growing in a closed greenhouse or indoors). Some plant varieties you should plant multiple times in your garden, such as zucchini, because the plants need to pollinate each other.
If you have further questions or problems, you can simply get in contact! We are happy to help via firstname.lastname@example.org.