You are right to be dubious. It isn't any kind of mint at all. Mojito mint is a hybrid Mentha x villosa and as such can't be reproduced from seed. To be sure of getting the true one you need to buy a plant. I'm afraid you're learning the hard way that eBay is not a reliable source of seeds. Many times it is downright fraudulent. We get lots of these queries every year from disappointed buyers.

If you can post with some closer pictures either here or on The Name That Plant Forum you can probably get an id. for your plants. If I was forced to give an id with no further information I'd guess at an Impatiens species aka Jewelweed.

I bought it from Etsy, not Ebay but either way you're right. I've contacted the seller and received no response. Looks like I've been had.

Sorry - misread the name. But caveat emptor still applies.

I agree with impatiens ID. I'm sorry that happened to you--that's dissapointing

I'm not sure how Etsy works, hopefully they have a way for you to leave a feedback rating so others don't go through the same ordeal.