Invalid bet persistence

[WyndonWheway]

I've got my default bet persistence set at SP, which works fine most of the time - but very occasionally I get the message above and the bets aren't placed. Any ideas why this should be?

[starter22]

Not sure if this is correct but could it be you are placing SP bets into
markets that do not have a Betfair SP?

[WyndonWheway]

Sorry, I should have said that it is UK & Irish horseracing - which I believe all have SP markets.

[WyndonWheway]

I wonder if it's when I've got tick offset in operation and the market goes in play just as the first bet is matched.

[The Geek]

That would be it, as SP bets are not valid once the market goes in play.