Logically refuting atheism in favor of agnosticism

[Falcon1511]

1. Humans are not omnipresent or omniscent

2. Without omnipresence or omniscence, one cannot know with absolute certainty whether or not there is or is not a God/Gods

3. Humans cannot know with absolute certainty whether there is a God/Gods or not.

4. If one cannot be certain of there being or not being a God/Gods, then one cannot logically be an atheist

5. Therefore it's logically invalid for one to claim they are an atheist.