Hi, my bad on the ‘family’ reference. It is the ‘teams’ package that I use, I just use it for my family. Like I mentioned before though, it is far more cost effective than the kSuite, which is targeted at businesses.
As for the transferring for data, this is possible via a feature in kDrive. It is capable of transferring from a number of cloud storage services, including OneDrive. You can get more info on that here: https://www.infomaniak.com/en/support/faq/2406/import-external-data-to-kdrive
I still have my OneDrive at the moment but aim to close this down. I use my Synology to synchronise the data between kDrive, OneDrive and my Synology for data safety. (Yes, this is overkill) I will eventually remove OneDrive from that as I get a better home cloud setup in place.
It has already been said but the company is complying in the sense that it is providing a solution whereby you can delete your account. That said, where you are unable to follow that process, they should offer you the same ability via email. Each company does things slightly differently but I would hazard a guess that an email stating that you find it more reasonable for the action to be carried out via email, they would be likely to comply.
The reasons why companies put these in place is simply to avoid mass requests for deletion and, as stated, to also protect you.
While email spoofing has been mentioned, it is somewhat unlikely anyone would send a request for deletion after spoofing your email, yet, it is not impossible.
You may have to be persistent, could use services that support or even get some pointers from the ICO. Here is a really good link https://ico.org.uk/for-the-public/your-right-to-get-your-data-deleted/
I wish you luck