Problems entering medical information

I am having the following issue when entering medical expenses.

1) For each of the following screens, there is a single text box which is prepopulated with $0, and the program wont let me change it.

Tell us about any prescription medication expenses - Prescription expenses

Tell us about anything spent on medical professionals -Medical professionals fees

Tell us about anything spent on medical facility fees - Medical facility fees

Tell us about anything spent on x-ray and lab work fees - Lab and x-ray fees

2) For the screen "Tell us about anything spent on medical travel," the text box "Miles driven to get medical care" is prepopulated with 0 (zero). It doesn't let me change it, and if I try to "Continue", I get the message
"Value must be greater than 0"