Error message- sorry only one allowed

We have been using an online form for families to register for upcoming stays at our Ronald McDonald House. It was working fine for the first 4 submissions. Then the fifth one tried an they get an error message "Sorry. Only one entry is allowed"

I upgraded our account to silver and it still gives that error message to a new form submission.

I assume you have figured this out. Based on the error message, this could be either you have set a submissions limit in your form or enabled unique submission. Anyway, upon checking your form, none of these settings were used now so your form should be working without that error.

Yes I did figure it out right after i sent the inquiry. Many thanks for
your kind and helpful reply.
...