EURO restriction created due to AIP rule.
What is available publicly on
https://www.nm.eurocontrol.int/RAD/ under EURO (excell worksheet EURO Restriction) is saying
In German AIP (if you have the access to it) route from MAKOT onwards is more or less only available below FL100. Now, it is the interpretation of IFPS how it sees your planned descend (as you wrote in FPL above) at MAKOT (G21
MAKOT/N0260F090 Z818 MANEM).
Have you tried to enter an earlier descent in FPL, for example ...UL47
GTQ/N0280F150 G21 MAKOT/N0260F090 Z818 MANEM.... ? (Using original C680 of course, not the 650)
Just to test it, at least...