LDAP Error and yarn start:dev error

[Мухаметали Кусайынов]

Hello dear colleagues!  I would be grateful if you could help with the difficulties I am having.
First) I add these values in [dspace-dir]/config/dspace.cfg allow it from this line:
plugin.sequence.org.dspace.authenticate.AuthenticationMethod =
org.dspace.authenticate.LDAPHierarchicalAuthentication

ldap.enable = true
And also these lines:
ldap.provider_url = ldap://10.5.0.25:389
ldap.id_field = cn
ldap.object_context = [КазНУ]
ldap.search_context = OU=Organizational Structure,DC=kaznu,DC=kz
ldap.email_field = mail
ldap.surname_field = sn
ldap.givenname_field = givenName
ldap.search_scope = 2
ldap.search.user = CN=Құсайынов Мұхаметәли,CN=Users,OU=Библиотека,OU=Common,OU=Organizational Structure,DC=kaznu,DC=kz
ldap.search.password =  password
ldap.netid_email_domain = @kaznu.edu.kz
But it gives me the following error:
DSPACE REST API! Response is not valid JSON!
Response returned:
{"timestamp":"2023-04-24T12:33:50.771+00:00","status":500,"error":"Internal Server Error","message":"Cannot load plugin class: java.lang.ClassNotFoundException:                                                                     org.dspace.authenticate.LDAPHierarchicalAuthentication","path":"/server/api"}
What am I doing wrong?

Second) When I type the command: yarn start:dev
Writes: Port 4000 is already in use. Would you like to use a different post?
I press yes. And it runs on a different local host. But with error: 500.
How to fix it?
Thank you very much.
Yours sincerely, Mukhametali.