Solr fails to load cores - solr

Question

I added a misconfigured dynamic field to a Solr Core. Since, I cannot update anything to fix this error because Solr fails to load it.
The erroneous query:
http://solr.dev.fr:8983/solr/zCollection/schema
{
"add-dynamic-field":{
"name":"*_alz*",
"type":"customFieldType",
"stored":true,
"indexed":true
}
The Exception :
org.apache.solr.common.SolrException:org.apache.solr.common.SolrException: Could not load conf for core zCollection_shard1_replica1: Can't load schema managed-schema: Dynamic field name '*_alz*' should have either a leading or a trailing asterisk, and no others.
The problem:
I can't find this dynamic field anywhere because I'm using data_driven_schema_configs
I can't use schema API to delete it; I get 404 Not Found in response.
The Question:
Where can I found this element and delete it?
PS: I did a
grep -rnw '/opt/lucidworks-hdpsearch/' -e '_alz'
But nothing comes out with me.
Update 1 :
I found the field in Zookeeper files using:
./zkcli.sh -zkhost hmaster.dev.fr:2181 -cmd list
I downloaded the file
./zkcli.sh -zkhost hmaster.dev.fr:2181 -cmd get /configs/zCollection/managed-schema
Fixed the erroneous fields and uploaded it to ZK again:
./zkcli.sh -zkhost hmaster.dev.fr:2181 -cmd putfile /configs/zCollection/managed-schema managed-schema
And it works finally!!