Dear Colleagues,

I have a problem interpreting confidence interval for vaxera and vaxera2017. What does (0 .) Confidence interval mean? .Or am I doing something wrong to get that confidence interval
below is my data and code

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Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input byte agegp int year byte vt double time int bcd byte ipd double(vaxera postslope vaxera2017 postslope2017)
1 1999  2  1  381  4 0 0 0 0
1 2000  7  2  437  8 0 0 0 0
1 2001  0  3  461  0 0 0 0 0
1 2002  6  4  354  7 0 0 0 0
1 2003  4  5  295  5 0 0 0 0
1 2004  3  6  379  5 0 0 0 0
1 2005  2  7  412  2 0 0 0 0
1 2006  2  8  418  4 0 0 0 0
1 2007  2  9  383  3 0 0 0 0
1 2008  1 10  371  2 0 0 0 0
1 2009  0 11  375  0 0 0 0 0
1 2010  2 12  415  3 0 0 0 0
1 2011  0 13  398  1 . . . .
1 2012  0 14  318  0 1 1 0 0
1 2013  0 15  291  0 1 2 0 0
1 2014  0 16  396  0 1 3 0 0
1 2015  0 17  410  1 1 4 0 0
1 2016  0 18  436  0 1 5 0 0
1 2017  0 19  153  0 1 6 1 1
1 2018  1 20  294  1 1 7 1 2
1 2019  0 21  419  0 1 8 1 3
2 1999  4  1 1070  8 0 0 0 0
2 2000  8  2 1113 13 0 0 0 0
2 2001 15  3 1034 18 0 0 0 0
2 2002  6  4  586  6 0 0 0 0
2 2003 10  5  765 12 0 0 0 0
2 2004  9  6  789 13 0 0 0 0
2 2005  9  7  651 16 0 0 0 0
2 2006  3  8  763  6 0 0 0 0
2 2007  9  9  542 11 0 0 0 0
2 2008  5 10  496  6 0 0 0 0
2 2009  4 11  540  6 0 0 0 0
2 2010  7 12  386  9 0 0 0 0
2 2011  2 13  397  4 . . . .
2 2012  1 14  268  4 1 1 0 0
2 2013  0 15  176  1 1 2 0 0
2 2014  0 16  298  3 1 3 0 0
2 2015  1 17  257  4 1 4 0 0
2 2016  1 18  194  1 1 5 0 0
2 2017  0 19   67  0 1 6 1 1
2 2018  1 20  227  2 1 7 1 2
2 2019  0 21  226  1 1 8 1 3
3 1999  5  1  867  6 0 0 0 0
3 2000 10  2  826 15 0 0 0 0
3 2001  8  3  903 14 0 0 0 0
3 2002  8  4  600  9 0 0 0 0
3 2003  8  5  675 10 0 0 0 0
3 2004  4  6  642  6 0 0 0 0
3 2005  4  7  500  8 0 0 0 0
3 2006  4  8  502  7 0 0 0 0
3 2007  7  9  448 10 0 0 0 0
3 2008  4 10  363  4 0 0 0 0
3 2009  7 11  465  9 0 0 0 0
3 2010  8 12  339  8 0 0 0 0
3 2011  3 13  270  3 . . . .
3 2012  0 14  203  1 1 1 0 0
3 2013  0 15  148  1 1 2 0 0
3 2014  0 16  206  2 1 3 0 0
3 2015  0 17  226  1 1 4 0 0
3 2016  0 18  184  1 1 5 0 0
3 2017  0 19   62  1 1 6 1 1
3 2018  2 20  194  2 1 7 1 2
3 2019  0 21  230  2 1 8 1 3
4 1999  5  1 1172  6 0 0 0 0
4 2000 10  2 1106 11 0 0 0 0
4 2001  9  3  996 14 0 0 0 0
4 2002  4  4  746  6 0 0 0 0
4 2003 16  5  899 20 0 0 0 0
4 2004  9  6  714 12 0 0 0 0
4 2005  4  7  546  5 0 0 0 0
4 2006  5  8  586  6 0 0 0 0
4 2007  8  9  459 10 0 0 0 0
4 2008  6 10  457  7 0 0 0 0
4 2009  4 11  499  5 0 0 0 0
4 2010 22 12  508 26 0 0 0 0
4 2011  6 13  373  8 . . . .
4 2012  2 14  228  2 1 1 0 0
4 2013  0 15  190  2 1 2 0 0
4 2014  1 16  374  5 1 3 0 0
4 2015  1 17  335  3 1 4 0 0
4 2016  0 18  215  2 1 5 0 0
4 2017  0 19   83  1 1 6 1 1
4 2018  0 20  290  1 1 7 1 2
4 2019  1 21  247  3 1 8 1 3
5 1999  6  1  504  8 0 0 0 0
5 2000 12  2  482 15 0 0 0 0
5 2001 12  3  447 16 0 0 0 0
5 2002 10  4  294 12 0 0 0 0
5 2003 14  5  372 16 0 0 0 0
5 2004 20  6  285 24 0 0 0 0
5 2005  5  7  319  5 0 0 0 0
5 2006  2  8  307  3 0 0 0 0
5 2007  6  9  294  7 0 0 0 0
5 2008  3 10  257  3 0 0 0 0
5 2009  3 11  290  5 0 0 0 0
5 2010 12 12  349 13 0 0 0 0
5 2011  1 13  303  1 . . . .
5 2012  1 14  204  2 1 1 0 0
5 2013  2 15  213  4 1 2 0 0
5 2014  3 16  404  7 1 3 0 0
end
label values agegp acat
label def acat 1 "<2m", modify
label def acat 2 "2-11m", modify
label def acat 3 "12-23m", modify
label def acat 4 "24-59m", modify
label def acat 5 "5-14y", modify
////My code
use cleaned_datafiles/final_grouped_data_censoredd,clear

keep if agegp==1

tsset time

gen bcdnopnm =bcd-ipd

gen log_ipd = log(vt+1)

gen log_other_bld_cul = log(bcdnopnm)

**testing common trend(Common trend assumption met)

glm vt time if vaxera==0, link(log) family(nbinomial) exp(bcdnopnm) eform

**Testing interaction(interraction not significant)
glm vt vaxera postslope vaxera2017 postslope2017, link(log) family(nbinomial) exp(bcdnopnm) eform

***Unadjusted model
glm vt vaxera, link(log) family(nbinomial) exp(midyrpop) eform

**Final model
glm vt vaxera vaxera2017 , link(log) family(nbinomial) exp(bcdnopnm) eform