Ok, I tried a search but didn't know the correct search terms for this.

I'm based in Canada and am trying to book a one-way intra-Germany flight (MUC - TXL) on the LH website. If I put my country of residence as Canada, a one-way flight option doesn't even appear.

If I use UK, then it appears. (More advantageous than saying Germany since I don't get dinged the 10 EUR surcharge.) However, when I enter my "personal info", my country of residence is already entered as UK.

My question is, does it matter? Let's say I put in my full Canadian address in the fields provided, will that be ok?

What I'm worred about is : 1) They may restrict me getting on the plane for security reasons, and 2) They may upcharge me for not being a resident of UK.

I tried using booking engines, such as Travelocity, and entered a Canadian residence but the price either doubles or goes up 5x (depending if it's LH or another code-share) for the same flight on the LH website.

Thanks in advance.