Need simple ways to adjust my temples!

[black glasses frames]

After these years of wearing, I found that the two temples of my reading eyeglasses are just not at the same line, the lenses are OK, it don’t cause me much trouble, but it makes me really uncomfortable as I feel the frame is aslant on my face, and sometimes, the frame seems to get off from my face easily, I have adjusted it several times by myself, but it came to the original shape soon, the frame was made by stainless steel material! I don’t want spent money on this piece of problem, just need some simple method.
Thank you!