i topped up £20 on id mobile app and its gone down to £14.88 and im frustrated as i was going to use that to get unlimited data as it ran out at 11:59pm

I topped my id mobile pay as you go sim hoping that they'd take it to purchase another unlimeted data but no I'm really annoyed and angry I tried contacting id mobile but wouldn't work there was no message to let me know where its gone too and I was hoping there's a way they'd give the money back so I can get my unlimeted data which I purchased a month before does anyone have any idea how I should go abroad dealing with this as I'm very frustrated and angry that my money been taken and no message as to what's been used or purchased as it can be add on as my unlimeted data has ended last night can I contact someone and see if I can get unlimited data as I thought the top up is were they'd take it for the unlimeted data so it carrys on but I don't know can someone help please and I can't stand those stupid dumb robots AI's as there useless