Recently, retailers have been experiencing from reloading via SMS, like not receiving confirmation, etc.. Here's the official advisory from LoadCentral:
We have been experiencing too much transactions that we have not anticipated. The volume of daily transactions are way above our projections for this year. Our tech team is disabling from time to time some tools on the web tools of our retailers, sub-dealers and dealers to avoid swamping the system. Rest assured though that we are doing something about it. We have already purchased new sets of servers, co-located another rack at e-PLDT’s Vitro Data Center and our programmers have been working on our new core for the past month. This new system core will address all the issues that we are currently facing. We are scheduled to deploy this by late November.

Please bear with us.