Do you have a copy of the agreement?
You will need a lawyer specific to the country it relates to.
This is not an Eu law question.
I assume it is Luxemburg. You can do a search via the law society / SRA and may find a dual qualified lawyer or a Luxembourg lawyer based in uk. Alternatively you will need to contact a lawyer based in Luxembourg to answer your question.
Eu law is not applicable to your question on the contract. Local law applies.
Please can you kindly accept my answer. Many thanks.