Missing ID between Accounts and Contacts ?

I have local SuiteCRM 7.5. 3 and Win10.

When I edit CONTACTS, I see that part of the Accountnames are empty , as per photo attached.

CompanyC field in CONTACTS is a customfield I created some time ago in Contacts, there I have the COMPLETE Account Names as well.

However apparently with import a few days ago, something went wrong

I have in “EDIT” CONTACTS in Company C(customfield) the correct Company aka Accountname.

But in EDIT Contacts there is an empty AccountName. BUT upon checking in ACCOUNTS… IT IS THERE !

So probably the IDs went wrong with Importing some days ago

How to repair that. ?

I did it by Copy/Paste and that works, but i have some 15.000 missing !

I can work with Access 2016 (make Query), Externale Data linking, and get Accounts,Accounts cstm and AccountsContacts (ID links) and Contacts and Contacts cstm.
But to make Criteria and Update is not yet successfull because the the “wrong” or missing ID linking.

Hope for solution from you !