On contribution page on my site, I entered 'other amount': $10. However, I did not select 'Other Amount' radio box. The default radio box ($25) stays selected. When the payment is submitted it sums the default and other amount and charges $35 rather than just the intended $10.
I'm not sure if this is the intended or not, but it seems unintuitive for an end-user. Any way to indicate that if 'other amount' is populated, to disregard the other radio boxes?
Are you using a price set? I believe that if you set the amounts directly in the Contribution Page settings, then when you click on the Other Amount field, the Other Amount radio button is selected, doing what you expect. If you aren't using a price set and this isn't working, please provide details on your version and CMS.
But if you're using a price set, then this doesn't work. That's because the Other Amount field isn't formally a separate other amount field in a price set - it's just a numeric price field with a $1 amount. I think it might make sense to make it possible to add a formal Other Amount field to price sets or otherwise figure out a way to make this work better, but that would require someone to take this on (or fund an expert to take it on).
I agree with Lars - the behavior you describe should be the default behavior on a contribution page without price sets, and it probably is worth comparing with a demo site to confirm the behavior.
If you are using a price set, one of the features of the Price Set Visibility extension is to automatically deselect another value if you select another amount. Note that this is finicky, and only works if there are two fields in the price set, the first is a multiple-choice field, and the second has a label of "Other" or "Other Amount".
