We lost our passports, so we couldn't enter the country and were held for 2 hours by the border police
We lost our passports, so when we tried to enter the country, we got stopped by the border police for 2 hours.
We are stucked by the border policeはちょっとわかりにくいですね。「2時間拘束させられた」と言いたい時に大体We were stopped by the border police for 2 hoursやwe were held by the border police for 2 hoursと言いますね。
We lost our passports, so we couldn't enter the country and--
パスポートなくして入国できずに
入国できずにの代わりに、「入国しようとした時にとめられた」みたいな言い方でもOKです→when we tried to enter the country, we got stoppedにしても良いです。
ご参考になれば幸いです。