MadScot
Brandy's back!
Trade embargoes should show on the F4 screen, if you select the 'trade' tab. (it looks similar to a military alliance on the 'treaties' tab, IIRC.
But that sounds like the AI doesn't trust you. If they wont take 250gpt from you, or wont take stuff from you with gpt involved, that almost certainly means your rep is trashed. Did you break any deals, attack without warning etc? Any of those can ruin your ability to trade over a timescale (as opposed to tech for tech swaps, where there is no trust required).
But that sounds like the AI doesn't trust you. If they wont take 250gpt from you, or wont take stuff from you with gpt involved, that almost certainly means your rep is trashed. Did you break any deals, attack without warning etc? Any of those can ruin your ability to trade over a timescale (as opposed to tech for tech swaps, where there is no trust required).