Fixed

    public void tagRmvlC2(TagNode currentNode,String tag,TagNode previousNode) {
        if(currentNode==null) {
            return;
        }
        else if(currentNode.tag.equals(tag)) {
            if(previousNode!=null) {
                if(currentNode.firstChild==null) {//When THE PICKED TAG HAS NO CHILD
                    if(previousNode.sibling!= null && previousNode.sibling.equals(currentNode)) {
                        previousNode.sibling=currentNode.sibling;
                        currentNode=previousNode.sibling;
                    }
                    else {//the previousNode is the parent
                        previousNode.firstChild=currentNode.sibling;
                        currentNode=previousNode.firstChild;
                    }
                }
                else {
                    if(previousNode.sibling!= null && previousNode.sibling.equals(currentNode)) {
                        TagNode tempNode=currentNode.sibling;
                        TagNode tempNodeTwo = null;
                        previousNode.sibling=currentNode.firstChild;
                        tempNodeTwo= previousNode.sibling;
                        while(tempNodeTwo!=null) {
                            if(tempNodeTwo.tag.equals("li")) {
                                tempNodeTwo.tag="p";
                            }
                            tempNodeTwo=tempNodeTwo.sibling;
                        }
                        tempNodeTwo= previousNode.sibling;
                        while(tempNodeTwo.sibling!=null) {
                            tempNodeTwo=tempNodeTwo.sibling;
                        }
                        tempNodeTwo.sibling=tempNode;
                        currentNode=previousNode.sibling;
                    }
                    else {//the previousNode is the PARENT SO THE CHILD OF THE
                        TagNode tempNode=currentNode.sibling;
                        TagNode tempNodeTwo = null;
                        previousNode.firstChild=currentNode.firstChild;
                        tempNodeTwo= previousNode.firstChild;
                        while(tempNodeTwo!=null) {
                            if(tempNodeTwo.tag.equals("li")) {
                                tempNodeTwo.tag="p";
                            }
                            tempNodeTwo=tempNodeTwo.sibling;
                        }
                        tempNodeTwo= previousNode.firstChild;
                        while(tempNodeTwo.sibling!=null) {
                            tempNodeTwo=tempNodeTwo.sibling;
                        }
                        tempNodeTwo.sibling=tempNode;
                        currentNode= previousNode.firstChild;
                    }
                }
            }
        }
            tagRmvlC2(currentNode.firstChild,tag,currentNode);
            tagRmvlC2(currentNode.sibling,tag,currentNode);
    }