Csdid: Unbalaced panel with covariates

[Dayla Spassio]

I have an unbalanced panel with observations at the provincial level from 2006 to 2023. I want to estimate the effect of a treatment that is introduced from 2014 onward. My empirical strategy is based on estimating a DiD and I was hoping to use command CSDID developed by FernandoRios based on Callaway and Sant'Anna (2021) to account for multiple time periods My baseline model is the following:

set seed 1
gen sample = runiform()<.9
csdid y if sample==1  , cluster(id) time(year) gvar(treat)

I then wanted to include a dummy variable equal to one for the years 2020–2021 (Covid-19 pandemic), but the results remain unchanged.

I suspect that this might be due to an insufficient number of observations during those years.

------------------------------------------------------------
       | first_t                                            
  year |   0   2014  2015  2016  2017  2018  2019  2020  Total
-------+------------------------------------------------------
  2006 |  10     1     2    30    25    10     7     4    102
  2007 |  11     1     2    30    25    10     7     4    103
  2008 |  12     1     2    30    25    10     7     4    104
  2009 |  12     1     2    30    25    10     7     4    104
  2010 |  12     1     2    30    25    10     7     4    104
  2011 |  12     1     2    31    26    10     7     4    107
  2012 |  12     1     2    31    26    10     7     4    107
  2013 |  12     1     2    31    26    10     7     4    107
  2014 |  12     1     2    31    26    10     7     4    107
  2015 |  12     1     2    31    26    10     7     4    107
  2016 |  12     1     2    31    26    10     7     4    107
  2017 |  12     1     2    31    26    10     7     4    107
  2018 |  12     1     2    31    26    10     7     4    107
  2019 |  12     1     2    31    26    10     7     4    107
  2020 |  12     1     2    31    26    10     7     4    107
  2021 |  12     1     2    31    26    10     7     4    107
  2022 |  12     1     2    31    26    10     7     4    107
  2023 |  12     1     2    31    26    10     7     4    107
-------+------------------------------------------------------
Total  | 213    18    36   553   463   180   126    72   1,908
------------------------------------------------------------

----------------------------------
       | first_t                
  year |  2021   2022   Total    
-------+--------------------------
  2006 |   11      2     102    
  2007 |   11      2     103    
  2008 |   11      2     104    
  2009 |   11      2     104    
  2010 |   11      2     104    
  2011 |   12      2     107    
  2012 |   12      2     107    
  2013 |   12      2     107    
  2014 |   12      2     107    
  2015 |   12      2     107    
  2016 |   12      2     107    
  2017 |   12      2     107    
  2018 |   12      2     107    
  2019 |   12      2     107    
  2020 |   12      2     107    
  2021 |   12      2     107    
  2022 |   12      2     107    
  2023 |   12      2     107    
-------+--------------------------
Total  |  211     36   1,908    
----------------------------------

Suggestions?
Thanks.