No bookmark returned, all ok and only first node out of 80 is created

I'm calling a procedure 80 times to perform queries with args, but only the first create is executed, when I look in the neo4j browser. Here is the code of the procedure:

    var savedBookmarks = []
    function op_modifyQuery(txc,query,args){
        return new Promise(function(resolve,reject){
            var session = driver.session({ 
                defaultAccessMode: neo4j.WRITE,
                bookmarks: savedBookmarks
            session.writeTransaction(function(tx) {
      ,args).then(function(result) {
                    var bm = session.lastBookmark();
                }).catch(function(error) {
                  console.error('Query failed!', error);
                }).finally(function() {
                }).catch(function(error) {
                    console.error('Session failed!', error);

The result output (truncated to 4 lines out of 80)

OK= 1 = [] CREATE (t:qSurvey {uuid:$topKeyParam,name:$nameParam} ) RETURN 'qSurvey' AS node,t.uuid,
OK= 2 = [] MATCH (t:qSurvey {uuid:$topKeyParam} ) CREATE (p:qPage {uuid:$pageKeyParam,name:$nameParam}) CREATE (t)-[r:hasPage]->(p) RETURN 'gPage' AS node,p.uuid,
OK= 3 = [] MATCH (p:qPage) WHERE p.uuid = $pageKeyParam CREATE (e:qElement {uuid:$elementKeyParam,type:$typeParam,name:$nameParam,title:$titleParam,isRequired:$reqParam} ) CREATE (p)-[r:hasElement]->(e) RETURN 'qElement' AS node,e.uuid,e.type,,e.title,e.isRequiered
OK= 4 = [] MATCH (e:qElement) WHERE e.uuid = $elementKeyParam CREATE (c:qChoice {uuid:$choiceKeyParam,value:$valueParam,text:$textParam} ) CREATE (e)-[r:hasChoice]->(c) RETURN 'qChoice' AS node,c.uuid,c.value,c.text

I assume, that the driver can only handle the first create, even if the arguments are all correct.
This code is my fifth rewrite doing separate sessions per query, before, I tried to use beginTransaction, but there I got error messages like "cannot commit a session in ready state".

Thank you for any help..
Oliver Weimar-Drese