Thanks again Jhieminga, you have delved admirably. When I left the Belgian company I closed down my bank account, mobile phone and moved from a shared house. I am fed up with the whole business and will write to the pension people to tell them that I am only contactable by mail. I receive a mailed certificate of life annually and will just have to find out what affects my pension as it happens. The whole business is one step forward and two back.
Now that Brexit has occurred, I have to complete a tax return, all in Flemish. I declare everything but they only tax Belgian sources of income.
i am about to write to them asking if they will tax it at source, just as they did with my salary because the fortnight it takes to complete the return is just too much.
I appreciate your efforts, thank you.