So when is the right time to upsell?

[afarigh]

So recently I tried to upsell to two potential buyers.

I had like a 10/10 rate of converting inbox enquires and I thought maybe I will try upselling since there were extra requirements. However, didn’t work out. I’m not sure it’s because of the timing of the offer or because of the upselling or mention of the price itself.

Any suggestions or experience?