Forms on interface needs to be able to update existing records AND create new records

It seems like you essentially need two types of forms.

One to update, and one to make a new record.

You already got the new record form sorted. As for updating, you could use the "open record details" option and make the fields editable.

Have a look at this workaround I made:
https://community.airtable.com/t5/show-tell/update-record-through-form-sorta/td-p/179052

You might be able to configure this to do what you're looking for?

If your users don't have Airtable accounts and you still need them to be able to update records, Airtable has a guide for that here: https://support.airtable.com/docs/use-case-update-records-via-a-form

It's for the old form view, but the logic still applies.  Might want to look into Fillout.com as well as that'd just work right out of the box

@Admin_LI 

There are 3 great workarounds for this limitation:

1. On the first form, give the user a link to the other form which will add new records to the linked table.

2. On the first form, in the linked record field, give the user an option to choose from that is called "new record" or something like that. Then, conditionally show additional fields where they can type in the new information. Then, use an automation to add the new record into the appropriate table.

3. Use Fillout's advanced forms for Airtable, which has this functionality natively built into its forms. Fillout offers about 500 advanced features that aren't natively available in Airtable's native forms.

Hope this helps! If you’d like to hire an expert Airtable consultant to help you with anything Airtable-related, please feel free to contact me through my website: Airtable consultant — ScottWorld

I get what you are saying! That brings up a follow up question. Is there a way to make fields in the "open record details" page ONLY editable by the assignee for that record?