I’m fairly certain if you contact customer service, or make a ticket to a GM, they will lock your account/game time. You’ll have to contact them again to get it unlocked. My brother has done this in the past. It was awhile ago though, so policies may have changed.
I did find this though from 2015 with a blue response regarding the topic.
Specifically:
Tiogaradh Customer Service 27567 posts
Hey Brawlwrecker,
There’s no way to pause a subscription but if something comes up and you can’t even log in for an extended period on prepaid game time then you should contact our support team and they will see what if anything they can do for you.
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