CF EZEIZA not responding on paid account

Hi,

I’m hosting two sites for Argentina audience, until last sunday traffic was server from EZE Colo, but now it’s being served by MIA colo, with a tenfold increase on response time.
I’ve checked a local newspaper website and EZE colo is responding so it’s working. I understood that free accounts does use all the colo’s but paid accounts do.
What can I do to recover my response time and get pages from EZE colo?

Thanks in advance