"recursiveLS" to "idpoly"

I am using the "Online Estimation" objects from the System Identification Toolbox.

I get the following error converting recursiveLS to idpoly:

obj = recursiveLS(2);
sys  = idpoly(obj);

Error using checkPolyValue (line 21)

Polynomial value must be a double row vector or cell array of double row vectors.

Error in idpoly (line 346)

A0 = A; A = checkPolyValue(A,'a',Ts);

The error does not occur if I use recursiveARMA instead:

obj = recursiveARMA([1 0]);
sys  = idpoly(obj)
sys =
Discrete-time AR model: A(z)y(t) = e(t)
  A(z) = 1 + 2.22e-16 z^-1 
  

The following section of the toolbox documentation indicates I should be able to convert between any "online estimation" object and an "idpoly" (https://www.mathworks.com/help/ident/ug/validate-online-parameter-estimation-at-the-command-line.html)

" To use offline commands, convert your online estimation System object, obj, into an idpoly model object. Also convert your stream of input-output validation data, Output(t) and Input(t), into an iddata object. "

sys = idpoly(obj);
sys.Ts = Ts;
z = iddata(Output,Input,Ts)