Help! My friend broke my game!

Hey I really need some help, I was playing with a friend who is a higher level than me (Im level 21 currently and he is level 32) and he was helping me complete "The Way Forward" quest in Act 2 in The Western Forest where you have to fight the black guards and put the thaumatic seal in the whole to open the pathway but I did not see any thaumatic seal and my friend explained to me that he got the thaumatic seal from one of the guards when he was playing alone but I did not see any thaumatic seal and my friend says he did not see any seal when he was with me nor does he have any in his inventory so please help!

This is a common bug, but I thought they fixed it. Maybe it's a new bug with different causes.

You can still get the Thaumetic Seal by killing the guard in a new instance. On the extremely unlikely off-chance that you read my post before the instance closes (less than 8-15 minutes after the area is empty), you will need to Ctrl+Left Click the transition to that area (whether it's the dot on your waypoint screen, or one of the archway-thingies that lead into the area) and then select the option that allows you to create a new instance.

If the instance has already closed (i.e. the area has been empty for 8-15 minutes or more), then you can just re-enter the area as normal and a new instance will automatically be created. Note that Ctrl+Click to access the Instance Manager is very useful, so you should still try it out even if you don't have to use it to fix this issue.

Then, you fight the guards again, and a Thaumatic Emblem (Seal? Emblem? I thought it was Emblem) will drop.

Happy hunting!