Field setting max size = 64KB uncaught exception

Attempt to update field json medium failed: Exception thrown while performing a schema update. SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'NOT NULL, PRIMARY KEY (`entity_id`, `deleted`, `delta`, `langcode`), INDEX `bu' at line 8: CREATE TABLE {node__field_json_medium} ( `bundle` VARCHAR(128) CHARACTER SET ascii COLLATE ascii_general_ci NOT NULL DEFAULT '' COMMENT 'The field instance bundle to which this row belongs, used when deleting a field instance', `deleted` TINYINT NOT NULL DEFAULT 0 COMMENT 'A boolean indicating whether this data item has been deleted', `entity_id` INT unsigned NOT NULL COMMENT 'The entity id this data is attached to', `revision_id` INT unsigned NOT NULL COMMENT 'The entity revision id this data is attached to', `langcode` VARCHAR(32) CHARACTER SET ascii COLLATE ascii_general_ci NOT NULL DEFAULT '' COMMENT 'The language code for this data item.', `delta` INT unsigned NOT NULL COMMENT 'The sequence number for this data item, used for multi-value fields', `field_json_medium_value` NOT NULL, PRIMARY KEY (`entity_id`, `deleted`, `delta`, `langcode`), INDEX `bundle` (`bundle`), INDEX `revision_id` (`revision_id`) ) ENGINE = InnoDB DEFAULT CHARACTER SET utf8mb4 COMMENT 'Data storage for node field field_json_medium.'; Array ( ) .