I cannot reproduce this as I don't have access to your data. Please create a minimal reproducible example for this to help me help you.
Trying similar code on the WWWusage dataset works fine:
library(forecast)
#> Registered S3 method overwritten by 'quantmod':
#> method from
#> as.zoo.data.frame zoo
trend <- seq_along(WWWusage)
fit1 <- auto.arima(WWWusage, d=0, xreg=trend)
fit2 <- auto.arima(WWWusage,d=1)
fc1 <- forecast(fit1, xreg=length(trend) + 1:10)
fc2 <- forecast(fit2, h=10)
autoplot(WWWusage) +
autolayer(fc2) +
autolayer(fc1)
Created on 2020-02-29 by the reprex package (v0.3.0)
Session info
devtools::session_info()
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