Hey there, HugoBruins.
Did you happen to have the old SSD connected to the motherboard during the Windows installation on the new SSD? It's not a rare occasion that some of the system files and/or partitions might get written on a secondary drive during a Windows installation process, that's why it's always recommended that you have all secondary storage drives disconnected from the mobo.
Try repairing your Windows via the installation media, to see if it fixes things up. Unfortunately if that doesn't help, you might have to do a fresh install once again. If you decide to do that and if you have data which you need to recover from that drive, you could use Ubuntu Live USB to access it and transfer the files to another HDD.
Hope that...