Line Chart - y scale or range

Line Chart - y scale or range

Hello,

I have data in a small range between 45.5 and 46.25, with two digits after the point. If I plot it in a line chart, the lower border is adjusted accordingly to 45.5, however, the upper border will be fixed to something like 48.5.

Due to this behavior, the peaks in the data are less visible than they would be on a smaller scale. Is there any possibility for me to either adjust the scale of the y axis, or its upper limit? Any help will be greatly appreciated.

Best Regards,
Jenny