You don't have permission to transcribe this page.

We have inherited a transcription project and I have been doing the digitizing and uploading using the omeka platform. The transcribing is being done with Scripto. Up until last week the people dong the transcribing were able to get on and work happily. But now all of the uploaded paged have “You don’t have permission to transcribe this page.” next to them.
The site is open and does’nt require a password so we can’t understand why the permissions have changed.
The only thing we have changed prior to this starting are the email addresses of the admin users.
Can anyone help?
Below is all of the system info in case it might help.
Thank you in advance

Browser Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.80 Safari/537.36
Role super
Omeka 2.5
PHP 5.6.38 (fpm-fcgi)
OS Linux 3.10.0-862.11.6.el7.x86_64 x86_64
MySQL Server 5.5.5
MySQL Client mysqlnd 5.0.11-dev - 20120503 - $Id: 76b08b24596e12d4553bd41fc93cccd5bac2fe7a $
PHP Extensions
Regular bcmath, bz2, calendar, cgi-fcgi, Core, ctype, curl, date, dba, dom, enchant, ereg, exif, fileinfo, filter, ftp, gd, gettext, gmp, hash, iconv, imap, intl, ionCube Loader, json, ldap, libxml, mbstring, mcrypt, mhash, mysql, mysqli, mysqlnd, odbc, openssl, pcre, PDO, pdo_mysql, PDO_ODBC, pdo_pgsql, pdo_sqlite, pgsql, Phar, posix, pspell, Reflection, session, shmop, SimpleXML, snmp, soap, sockets, SourceGuardian, SPL, sqlite3, standard, sysvmsg, sysvsem, sysvshm, tidy, tokenizer, wddx, xml, xmlreader, xmlrpc, xmlwriter, xsl, Zend Guard Loader, Zend OPcache, zip, zlib
Zend the ionCube PHP Loader, Zend Guard Loader, Zend OPcache
AdminImages 1.3
ArchiveRepertory 2.14 (inactive)
BagIt 2.0.1 (inactive)
BulkMetadataEditor 2.3
CSSEditor 1.0.1
Coins 2.0.3 (inactive)
CollectionTree 2.1
CsvImport 2.0.4
CsvImportPlus 2.3
DocsViewer 2.1 (inactive)
Dropbox 0.7.2
DublinCoreExtended 2.2
ExhibitBuilder 3.3.3 (inactive)
Export-2.0 2.0
GuestUser 1.1.1
HideElements 1.3
HistoryLog 2.6
ItemOrder 2.0.2
ItemRelations 2.0.2
OmekaApiImport 1.1.2
RecordRelations 2.0.1
RedactElements 1.0
Scripto 2.2
SimpleContactForm 0.5
SimplePages 3.0.8
SubjectBrowse 2.3
UserProfiles 1.1.1
Zoomit 2.0
avantgarde 1
berlin 2.4
bigstuff 1.0
default 2.4
scribe 2.0 (current)
seasons 2.4

It might be an issue with the cookie prefix - check out this forum thread and this thread for more information, as well as the documentation for configuration settings