Update collection

public class RecruiterProfile
    {
        public RecruiterProfile()
        {
            this.JobOffers = new HashSet<JobOffer>();
            this.Matches = new HashSet<Match>();
            this.Messages = new HashSet<Message>();
            this.DislikedJobSeekers = new HashSet<int>();
            this.LikedJobSeekers = new HashSet<int>();
        }

        [Key]
        public int RecruiterProfileId { get; set; }

        public string UserId { get; set; }

        public virtual User User { get; set; }

        public virtual ICollection<JobOffer> JobOffers { get; set; }

        public virtual ICollection<Match> Matches { get; set; }

        public virtual ICollection<Message> Messages { get; set; }

        public ICollection<int> DislikedJobSeekers { get; set; }

        public ICollection<int> LikedJobSeekers { get; set; }
    }

[HttpPut]
        public IHttpActionResult Like(int id)
        {
            var recruiter = this.data.RecruiterProfiles.All()
                .FirstOrDefault(x => x.UserId == this.CurrentUserId);

            if (recruiter == null)
            {
                return this.BadRequest("You must be a recruiter to do this.");
            }

            if (recruiter.LikedJobSeekers.Contains(id))
            {
                return this.BadRequest("You've already liked this guy.");
            }

            if (recruiter.DislikedJobSeekers.Contains(id))
            {
                recruiter.DislikedJobSeekers.Remove(id);
            }

            recruiter.LikedJobSeekers.Add(id);
            this.data.RecruiterProfiles.Update(recruiter);
            this.data.SaveChanges();

            return this.Ok(recruiter);
        }