I doubt changing the registra would change anything, as this seems more likely a problem on the TLD backend side than a problem on the registra itself, since it

I doubt changing the registra would change anything, as this seems more likely a problem on the TLD backend side than a problem on the registra itself, since it affect not only Gandi but also Route 53 Domain Registration. I'm under a serious consideration to switch from .ch to something else.