One of my client received summons from GST notice for 19-20 . but is accountant was hospitalized , if the client have any possible to ask time in gst DC.
As per Section 70 of CGST Act the summon issued indicate the name of offender & the recipient of summon must know by whether he is accused , Co-Accused or as witness.
As per Instruction No. 03/2022-23 , atleast 3 summons at reasonable intervals can issue.
But as per your query I assume the summon issued to your client is neither in capacity of Accused nor witnessed, it basically scrutiny of Return notice .
In few states department is issuing summon for scrutiny of returns.