This is a tip for new seller. Do not do any work for any buyer until you both agree and the buyer accept your offer or place order. You would only get used by the buyer then probably block you.
This happened to me and will never happen again. The buyer contact me and we both chat and come to conclusion, then I created a custom offer for the buyer. He then requested that I complete the work before he accept my offer. Which I did believing in his fake promise. Immediately I finished the work, he blocked me.
I have learnt from that and to ensure it does not happen to another seller, I decided to share the experience.
