To clarify players get a penalty if…
- They fail to connect at the start of the match by the time the “Prepare to Attack/Prepare your defenses” phase begins or if they leave at any time before dealing any damage or healing. The match automatically cancels in this case as a benefit for the remaining team members so that they do not have to play a person down from the start of the match.
- If the above condition is not fulfilled, a player will be penalized if they leave and fail to return within two minutes of total game time (including any breaks between rounds), even if they return and win the game. A player will NOT be penalized and will continue normally if they do return within two minutes.
These rules are more designed for the benefit of the remaining players rather than the disconnecting player. It is more important if you encounter an issue, to try and finish the current match, but then not immediately requeue for an new Competitive game until you take the time to do the troubleshooting. Unless you can provide more details about your connection issues such as performing a WinMTR test, there is nothing more that we can do.
Details on Blizzard Policies regarding Competitive Penalties: