tRPC "Cannot destructure property 'client' of 'useContext(...)' as it is null"

TypeError: Cannot destructure property 'client' of 'useContext(...)' as it is null.

export const getProjects = publicProcedure
  .input(z.object({ publicKey: z.string() }))
  .mutation(async ({ input, ctx: { prisma } }) => {
    const projects = await prisma.project.findMany({
      where: {
        client: {
          public_key: input.publicKey,
        },
      },
      select: {
        name: true,
      },
    });

    return projects;
  });

const { mutate } = api.client.getProjects.useMutation();