Causal Fallacy
Neglect of a Common Cause
Claiming that multiple events have distinct causes when the evidence suggests or is compatible with all the events having the same cause.
Also see Correlation vs. Causation Fallacy.
When I get out of bed, my dog outside also gets up and begins barking. I conclude that my getting out of bed wakes up my dog. In reality, it is likely the rising sun also wakes him up.