this is a static issue. You have four options.
1. If possible, use another printer.
2. Put 20 sheets of normal copy paper underneath the Flex-Soft foil to avoid static electric loading when pulling the paper inside the printer.
3. Print from the normal printer driver (not through the TransferRIP)
4. Print your design with the media setting “Labels 1” on the B-Paper in non-mirror mode. Then use an empty foil and put them in the heat press like you would do if you print on the foil. All settings are the same in this case. Nothing is changing except of the printed media and the mirror mode.
NOTE: This is a risky procedure. In worst case the B-Paper can jam in the fuser unit and you have to replace it. But we have tried it here with the ES7411WT without any problems.
Hope one of my tips will lead to a succesful result.