Hi. I'm using iPhone 4S running ios 9.3.5 and I tried to activate imessage. The status of the imessage is 'waiting for activation'. I noticed that i keep receiving sms from 68886 with strange long text starting with REG-RESP?v=3;r*******. Each sms i received from this number is charged on my digi acc. I have tried all the method like switching airplane mode on/off, reset network setting, log in/out of my apple id but the imessage still in 'waiting for activation' status. Please help.