My entry will not save
A refused save is almost always one of five things: a required field left empty, a value outside a field's allowed set, a duplicate in a field that must be unique, a link pointing at something that does not exist, or — for bookings — a slot with no capacity. The message names the field; fix that field rather than retrying.
You fill in a record, save, and it comes back refused. The refusal is deliberate — the entry is checked against the rules of its collection before anything is stored, and the message names the field that failed. Start there rather than retrying the same save.
1. A required field is empty
Some fields are marked required, meaning an entry is meaningless without them. Required fields are enforced when an entry is published; a draft can be saved with them still empty. So this refusal usually means you are saving a published entry — or working in a collection that saves new entries as published by default, such as the companies, contacts, leads, and deals that come with a new business. Fix: fill it in, or save the entry as a draft and finish it later. If a field is required but you genuinely do not have the value at the time of entry, that is a signal the field should not be required — change it on the collection rather than inventing placeholder values.
2. A value is outside what the field allows
A field with a fixed set of options accepts only those options, and a typed field accepts only that type — a number field will not take text, a date field will not take a loose phrase. A name must be at least three characters. Fix: choose from the allowed values, or correct the format. If the value you need genuinely is not among the options, add it to the field's options rather than forcing it elsewhere.
3. A unique field already has that value
A field marked unique cannot repeat across entries — an order number, a code, an email that must identify one record. Fix: search the collection for the existing entry. Nine times out of ten the record already exists and you are creating a duplicate; update the existing one instead. The details are in duplicate value on a unique field.
4. A rule limits which entries a link can point at
A reference field can carry a rule that narrows what it accepts — for example, the vehicle on a work order must be one of the vehicles belonging to the customer already chosen on it. Pick a vehicle that belongs to someone else, and the save is refused. The same rule refuses the save when the field it depends on is still empty, or points at an entry that has since been archived. Fix: set the field the rule depends on first, then pick from what it allows. If nothing is allowed — the customer has no vehicles yet — add the missing entry and link it before trying again.
5. The booking slot has no capacity
If the collection takes bookings, a save can be refused because the time asked for is not available — outside the department's working hours, or already full. Fix: check the department's hours and existing bookings for that slot. If nothing at all is bookable, the working hours are probably not set — see set up locations, departments, and working hours, and create a booking for the reasons a booking is refused.
Still refused?
Two less obvious causes. A computed field cannot be written to — rollups and lookups are calculated, so filling one in by hand or through an import is refused by design; leave them alone and let them update. And a locked field: a field rule can make a field read-only while a condition holds, and any change to it is refused until the condition no longer applies.
Related
Field types and their settings are covered in fields: built-in and your own and create a collection; the difference between linking and computing in reference vs multi-reference and rollup vs lookup. The full sequence of a save is in create an entry.