Hello CONN experts!

I'm new to using CONN and would greatly appreciate any advice you may be able to provide. I'm working with a dataset of 14 subjects with 1-2 resting-state runs. I had no problems importing/ uploading my structural data for each participant. However, when I try to import my functional data for subjects 2-14, I get the following error:

Error using spm_sample_vol
Unknown datatype.

Error in conn_fileutils (line 454)
 else [varargout{1:nargout}]=spm_sample_vol(V,varargin{2:end});
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error in conn_menu>conn_menu_selectslice (line 1280)
 case 3, y=[]; for nv=1:numel(x.vol), ty=reshape(conn_fileutils('spm_sample_vol',x.vol(nv),reshape(x.x(:,:,n),1,[]),reshape(x.y(:,:,n),1,[]),reshape(x.z(:,:,n),1,[]),1),x.dim([1 2])); y=cat(4,y,ty(end:-1:1,end:-1:1)'); end
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error in conn_menu (line 924)
 title=conn_menu_selectslice(data.x1,data.n,data.view); 
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error in conn (line 2754)
 conn_menu('updateimage',CONN_h.menus.m_setup_00{5},cfile{3});
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
CONN22.v2407
SPM25
Matlab v.2025b
project: CONN22.v2407
storage: 346.5Gb available

This error did not occur for the first subject, and the NIfTI files for other subjects do not seem to differ from the first subject in terms of scanning parameters or file type. As such, the "unknown datatype" message is puzzling. I have re-installed the most recent version of SPM and re-set the path in Matlab, but the error still remains. 

Thank you in advance for your help! 

- Natalie