FRUSTRATED

I am truly frustrated with RCS. I had a account with them years ago and never experienced this. I very recently opened a account again. I used my card and when i tried to use it again they blocked it then the ***** department called me and they reactivated it. Today i used it first transaction went through and when i tried to use it again it declined because they blocked it. Why???? Now they want to open a investigation! For what??? I have my card I used it myself and made a payment. Whats the point of having this card if its going to continuosly be blocked after a transaction??? I will be clearing the balance and close this account! Useless.