WordPress, Error when trying to insert data >> Notice: wpdb::prepare was called incorrectly

I have fixed this, the issue was in the way I was creating the array. I was using a multi-dimensional and needed to call the correct level of the array in the post.

By calling

$_POST[‘customer’]

which was the name of the array I could access the correct rows. Here is what the array looks like. Quite painful but I solved it in the end so wanted to ensure I shared for others.

Array ( 
[customer] => Array ( 
    [0] => Array ( [customer_id] => 6 [locations_id] => 1 [funding_source] => 2 [attend_date] => 2018-02-12 [approval_date] => 2018-02-12 ) 
    [1] => Array ( [customer_id] => 2 [locations_id] => 1 [funding_source] => 1 [attend_date] => 2018-02-12 [approval_date] => 2018-02-12 ) 
) 
[approve_data] => Approve Attendance )