cannot get data of column #id

I want to echo some values of a query

while(odbc_fetch_row($tableX)) 
{	  
  for($i=1;$i<=odbc_num_fields($tableX);$i++) 
  {
    if ($i==1)
	{
	  echo odbc_result($tableX,1); //echoed
	  echo odbc_result($tableX,2); //echoed
	  echo odbc_result($tableX,21); //echoed
	  echo odbc_result($tableX,22); //echoed
      var_dump(odbc_result($tableX,22)); //returns values
	}
	else if($i==2)
	{
	  echo odbc_result($tableX,$i).'++';
      var_dump(odbc_result($tableX,22)); //returns bool(false) and empty rows	  
	}  
	else if($i==3)
	{
	  echo odbc_result($tableX,$i).'+';	  
	} 
	else
	{
	  echo odbc_result($tableX,$i); //($tableX,1) ($tableX,2) ($tableX,3) echoed ($tableX,21) ($tableX,22) not echoed
	}
  }
}

As I indicated in the comments, some of the odbc_result's raises an error:

> cannot get data of column #21
> cannot get data of column #22

I (am not sure but) think the issue is:
> An error occurs if a column number parameter for a field is less than
> one or exceeds the number of columns (or fields) in the current
> record. Similarly, an error occurs if a field with a name that is not
> one of the fieldnames of the table(s) that is(are) being queried.

Yet, I couldn't see the reason.
Thanks in advance.

Edit: Else works if I delete the echoes under if ($i==1)
Both 21 & 22's data type is NCLOB

Fixed it by converting NCLOBs (odbc_result($tableX,21) and odbc_result($tableX,22)) to nvarchar

CAST(BINTOSTR(CAST("COLUMNNAME" AS binary)) as nvarchar)