Yes.
Anyone or any organization can submit multiple solutions to the same challenge. Topics are often complex, seeking many components to integrate into an overall solution, ways to integrate components together, or multiple discrete solutions. It is reasonable that individuals and companies could have multiple solutions. In past challenges, companies with multiple solutions have been selected to present one or more of their solutions at the challenge showcase.
However, each solution submitted by the same company must be materially different and specific to the topic.