Radio button accept just first selection on mobile website for iPhone

Question

I developed a mobile website to be accessable by mobile devices, mainly iPhone and Android devices. And, to select the type of search to perform, I created 4 radio buttons. But, on iPhone when the user makes the first choice and try to choose another type of search, the radio button clicked just don't get selected! It's looks like a bug on iPhone radio button handling.

Does anyone already had a similar problem?

Code:

<li><label for="busca_tipo_empresas"><input type="radio" name="busca_tipo" id="busca_tipo_empresas" value="PSER">Empresas, produtos e serviços</label></li>
        <li><label for="busca_tipo_pessoas"><input type="radio" name="busca_tipo" id="busca_tipo_pessoas" value="NOME">Buscar pessoas</label></li>
        <li><label for="busca_tipo_enderecos"><input type="radio" name="busca_tipo" id="busca_tipo_enderecos" value="ENDE">Endereços</label></li>
        <li><label for="busca_tipo_delivery"><input type="radio" name="busca_tipo" id="busca_tipo_delivery" value="DELI">Delivery</label></li>

Webiste url: www.eversource.com.br/netsabe

Thanks Neto Marin