Are you having these issues just with Orbot or any VPN? Also, are you able to connect via other iOS nostr apps (Damus or Nostur)?
Discussion
1.8.6 works fine with nostr:npub168euw93e4cam59llcmydav0akwjk2p4nfy3p85pn22xv9y2jxuzq4s9uaw
Add tor relays
Which of yours are Tor? 
Everything except damus
I cannot connect to these 2 with my Mullvad VPN on. But this reminds me of Tor browser for Windows advising not to use VPN simultaneously unless you’re an advanced user. Which, to me, implies complex manual configuration.
Not sure if that complexity is involved with Orbot + Primal iOS + Tor relays. 