Getting only one row from a loop in php and mysql - php

Question

Hello family i have a big problem, i want to send the notifications to all the users who have commented on a certain post. Now the problem is that when i loop out the data i am finding a issue that some user id's are coming more than one time so my code is sending multiple notifications help me out here is the code:
//Inserting notifications to thread participants
$communityc = "SELECT * FROM communities_comments WHERE community_data_id=? AND commenter_id<>?";
$stmtcommunityc = $this->connect()->prepare($communityc);
$stmtcommunityc->execute([$CoumunityDataId,$CommenterId]);
$rowcommunityc = $stmtcommunityc->fetchAll();
$ownerIdc = $rowcommunityc['created_by'];
$community_idc = $rowcommunityc['community_id'];
foreach($rowcommunityc as $commentsrow){
$userId = $commentsrow['commenter_id'];
if($commenter_id != $ownerId){
$notify = "INSERT INTO alerts
(uid,username,alert,alert_status,alert_time,receiver_id,rdr_link)VALUES(?,?,?,?,?,?,?)";
$stmtnotify = $this->connect()->prepare($notify);
$stmtnotify->execute([1945,'batcall', 'There are some updates on one of the threads that you are a pacrticipant.', 'unread',$current_time, $userId, '../../community/single.php?id='.$CoumunityDataId.'']);
}
}