Sorry I can't help you, but I have had this problem so often myself.
I have had powder compacts that I can't open, I asked my husband to help and he forced it open with something out of his tool box and I had no alternative to keep it open permanently.
Atm I am struggling with a plastic tub of baking powder, normally I leave it partly open as it's the only way I can use it. Someone has very helpfully pushed it right down and I cannot open it for love nor money so I had to make my cake without this essential ingredient!
I have no idea why manufacturers make it so difficult to use their products.
I wish you the best of luck!
