What can I do if a Tim Horton's refuses to hire me because of my headscarf?

The manager at Tim Hortons (in canada) said that I cannot wear my headscarf the way I wear it (covering my hair and neck). He said I have to wear it tied back, like in a bun, or else I cannot work there. He claimed that it looks more "professional" and people have complained about females wearing the headscarf the way i wear it, but I really beleive he is bullshitting about that part. It angers me so much that this happened. I really don't want to leave the situation like this, untouched, but i have no idea what I can do. If i call the head office, what would they do about it? i'd appreciate any advice, thanks in advance for any help