Water heater keeps trying to light

[Easydoesit]

We just purchased a 273QBXL 2017
When the water heater turns on it keeps trying to light itself repeatedly unless the cover is off. It runs perfectly when the cover is off but when the cover is put back on it keeps trying to restart the flame. Like it's starving for oxygen. I've changed the tanks 3 times. In between each change if let it run for long periods to bleed out the previous gas, with the cover off. I can prop the bottom of the cover open and it sort of runs ok but sporadically try's to relight it self.

[SeaDog]

What sort of cover do you have on your water heater could you provide a pic? It seems to me the cover is not venting as it should.

[5picker]

Is it a tank water heater or tankless?
Posting the make/model of the appliance will get you better answers.