How do I stop data feeding through to blank fields?

[LizzieU]

I have one table (Table A listing members) with some fields being fed by other tables (call them B, C, D e.g. landlines) on a one-to-many relationship. I don't have data for all the entries in Table A that are fed from Tables B etc. (E.g. not all members have provided their landlines, but two members might have the same landline if they live together).

I am entering data for a new member in a form, but when I enter a new landline (on the same form), this then feeds through to all other members who haven't provided a phone number.

How do I stop this? (Sorry this is probably simple, but I haven't used Access for about 8 years)
Thanks

[orange]

It seems that you have a data structure(design) issue. It would be helpful if you could describe your application in plain English. Getting your tables designed to match your requirements is critical. Knowing how the other tables fit into the picture would help readers understand.
Good luck.

[LizzieU]

Thanks. I'll try, I don't think my terminology is up to scratch.

The database is primarily designed to hold a list of members and various details about them, so that I can produce queries that will help me run my group and make my admin a lot easier, produce reports etc. It was originally in excel, but that no longer fits my needs.

tbl_A has fields ID, Name, DOB etc as well as Class_ID, Subject_ID, Contact_ID etc which are linked to tables with unique IDs, and the relevant fields. So in tbl_subject there is a field Subjects which can be Maths, English or Both. Each member has one of these entries but can't have more than one. In tbl_Contact the parents' contact details were held, link by a one to many relationship with tbl_A (one entry in tbl_Contact to many in tbl_A).

But I was finding that when I entered a new member in into frm_A, default data was automatically appearing and where I had an existing member with missing data, the new member's details were replicating themselves to fill in missing data in a different member's record.

(Tried to replicate this to explain it better, but am now getting the message 'Cannot add record(s), join key of table 'tbl_A' not in recordset, but that's another issue.)

[orange]

I'm going to suggest you work through this tutorial from Rogers Access library. It's paper based, but leads you from a description of your "business" through a process to identify entities, attributes and relationships. The end result will be a database model that matches the business description. It will serve as a blueprint for your database.
It is similar - generally - to your "business" and what you learn by working through the tutorial can be applied to your situation. It will take about 30-45 minutes to do the tutorial. Perhaps the best use of 30 minutes in developing your database.
The Hernandez Method is a great reference.

Good luck.