It's a quite common thing, especially on older machines. There's often no zero, and no exclamation mark too: the goal is to have more room for other signs, make the machine less heavy and less costly.

To type a 1 on a machine like that, just type a minuscule “L” (I bought my machine in 202l is almost indistinguishable from I bought my machine in 2021 on a typewriter). For zero, just type a capital O, and for exclamation mark, a point, a backspace and an apostrophe.