Hi guys.

I've searched all over for this, and can't seem to find a way to get around. So I thought I'd just ask the question myself.

I have a Samsung Galaxy S4mini, and the network that I am on doesn't have the best coverage, so sometimes it will go out of range and disconnect from the Mobile Network.
The problem is that I accidentally selected the wrong network manually once. Now every time my real network goes out of range, it will select this other network that I accidentally clicked once. It will then just stay on this network (without my knowledge) until I realise my phone isn't working and have to manually search and select the correct network again.

My question is this: Is there any way to make my android phone forget that I have clicked on that wrong network and never try to automatically connect to it? I want it to only know about the one network. Then when it's out of range, it just has no signal, but connects again when I am in range.