Gmx wham input/output error in umberella.tpr file

I did umbrella sampling and generated 80 windows, and when I performed gmx, wham, but I am getting input/output error in the tpr files. Any help to resolve this error would be helpful.
PS: All tpr files are present, and path given is correct

gmx wham -it tpr-files.dat -if pullf-files.dat -o -hist -unit kCal

Found 80 tpr and 80 pull force files in tpr-files.dat and pullf-files.dat, respectively
Reading 80 tpr and pullf files
Automatic determination of boundaries…


Program: gmx wham, version 2021.4-Ubuntu-2021.4-2
Source file: src/gromacs/utility/futil.cpp (line 481)

File input/output error:
umbrella1.tpr