Onlyoffice in subfolder if seafile in subfolder

hello! I tried to setup onlyoffice by manual. welcome page works. editor open well. but documents not.
error: could not be saved
is it possible? and how if yes.

location /seafile {
    add_header X-Frame-Options DENY always;
    fastcgi_pass    127.0.0.1:8000;
    include  sites-available/cimm.locs/https/seafile.params;
    error_log       /var/log/nginx/seahub.error.log;
}

location /seafdav {
    fastcgi_pass    127.0.0.1:8081;
    include  sites-available/cimm.locs/https/seafile.params;
    client_max_body_size 0;
    error_log       /var/log/nginx/seafdav.error.log;
}

location /seafhttp {
    rewrite ^/seafhttp(.*)$ $1 break;
    proxy_pass http://127.0.0.1:8082;
    client_max_body_size 0;
    proxy_set_header X-Forwarded-For $remote_addr;
    proxy_connect_timeout  36000s;
    proxy_read_timeout  36000s;
    proxy_send_timeout  36000s;
    error_log       /var/log/nginx/seafhttp.error.log;
}

location /seafmedia {
    alias /www/seafile/seafile-server-latest/seahub/media/;
}

seafile.params:

fastcgi_param   SCRIPT_FILENAME     $document_root$fastcgi_script_name;
fastcgi_param   PATH_INFO           $fastcgi_script_name;

fastcgi_param   SERVER_PROTOCOL     $server_protocol;
fastcgi_param   QUERY_STRING        $query_string;
fastcgi_param   REQUEST_METHOD      $request_method;

fastcgi_param   CONTENT_TYPE        $content_type;
fastcgi_param   CONTENT_LENGTH      $content_length;

fastcgi_param   SERVER_ADDR         $server_addr;
fastcgi_param   SERVER_PORT         $server_port;
fastcgi_param   SERVER_NAME         $server_name;
fastcgi_param   REMOTE_ADDR         $remote_addr;
fastcgi_param   HTTPS               on;
fastcgi_param   HTTP_SCHEME         https;

onlyoffice:

location /office/ {
    proxy_pass http://127.0.0.1:88/; # THIS ONE IS IMPORTANT ! - Trailing slash !

    proxy_http_version 1.1;
    proxy_read_timeout 3600s;
    proxy_connect_timeout 3600s;

    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection $proxy_connection;
    proxy_set_header X-Forwarded-Host $the_host/office; # THIS ONE IS IMPORTANT ! - Subfolder and NO trailing slash !
    proxy_set_header X-Forwarded-Proto $the_scheme;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}

maps.conf:

map $upstream_http_strict_transport_security $strict_transport_security {
    '' max-age=31536000;
}

map $http_upgrade $connection_upgrade {
    default upgrade;
    '' close;
}
# Required for only office document server
map $http_x_forwarded_proto $the_scheme {
    default $http_x_forwarded_proto;
    '' $scheme;
}

map $http_x_forwarded_host $the_host {
    default $http_x_forwarded_host;
    '' $host;
}

map $http_upgrade $proxy_connection {
    default upgrade;
    '' close;
}

If you see error: “could not be saved” it means that the URL for saving a file is wrong. When the Doc Server tries to create a request to save the file it gets “error: 0”

Yes. But why?