Record is too large 3047

Hello

I have a database of courses at a University which has 8 tables each with a unique course code that I have used as the primary key.

All tables are linked using the same key - course code.

I have a form which contains 54 fields (these 54 fields are divided into 8 tables)

However when I try to update a record using the form, I keep getting this error:

Records is too large (3047) You defined or imported a table with records larger than 4K

Please can someone help?

I'm teaching myself Access so please be kind if I'm doing something stupid