Since the problem started when the low beam bulb was replaced I suspect that the bulb is not seated. The inclination of the beams relative to each other is set by the headlamp housing so when you move the housing both will move together. Since you rejected my eariler answer there is no way for me to respond in that thread as I asked you if you had further questions to please ask.
JA site administration asks that all communication for a single question be kept in the same thread.
If you have a 2006 USA spec Forester the information I posted is for your vehicle.
If you have the vehicle that was manufactured for some other country or is for another year the information will not apply.
Instead of rejecting the answer please allow me to reply to your questions and concerns so that you will get the answer you asked for
The only information I have for you is what I have posted so I am going to OPT OUT of this question and allow other experts to see it and they may be able to help you further