Goodcook Ceramic Mug with Vented Lid, 20oz

I was hoping to use these for taking soup to work. They will be fine as long as it is frozen and doesn't thaw until I am at work. I tested these when they arrived and they do not seal sufficiently to contain liquid. One leaked at the edge of the seal and the other leaked through the vent if the lid was even gently touched.

I've had a problem with the lid. I have 2 mugs and both became warped and cracked. No one had told me I couldn't put them in the microwave, after all isn't that what the vent is for? I complained and was sent 2 new kids and within 4 uses one is already cracked and unusable. And it never went into the microwave or dishwasher. Terrible quality.