wallpapering over a settling crack but paper has rippled

[Deansplit]

I have papered a feature wall which had a settling crack from being replastered from bare brick. The crack is at the corner of an archway, going diagonally upwards. I let the crack settle for a year, have filled it and kept an eye on it to notice when it's settled as much as I think it's going to. I filled one more time before papering and 3 days after, the paper has rippled along the crack line. I know the crack couldn't have opened up as I said, I'd noticed it getting to a minimal width then filled anyway. If anything, being that it's rippled, I presume the crack's compacted? Will this always be an issue or is there a way around this? It's a Victorian home so I know lime mortar moves/flexes more than sand and cement, but the wall's scratch coat and base coat is sand and cement.