Hi, I purchased a new ebike last Thursday, I have only done 6 miles to try it out. Its a lovely bike but just not for me. The retailer is unable to take it back unfortunately, however is happy to honour the warranty to another purchaser. Does anyone know of anywhere that I can advertise this successfully?

Several possibilities, however, that would depend on where you are located, whether you intend to box it up for shipping, and maybe just a little bit on what kind or type or capability your bike is, and the approximate selling price, also what degree of loss you are willing to absorb.

For me, six miles isn’t enough time to determine whether or not something “is for me”. Heck, thats barely a test ride...
What, exactly is it that doesnt work for you? Many nuances can be adjusted, upgraded, or simply gotten used to.
Or, is it a broader problem; ie an e-bike, any e-bike isnt going to accomplish the goal you had for it, etc?