Welcome to Smogon! Take a moment to read the Introduction to Smogon for a run-down on everything Smogon, and make sure you take some time to read the global rules.
Let your opponent know exactly what times you're available this week and during the extension period (next Wednesday) so maybe an overlapping time can be found. It will be much better if you two can find a time for the game to be played than having it go to an activity decision.