My house was taking a long

My house was taking a long time to sell and Parkers approached us to assist. On initial contact the context given by their representative was regarding entering into a joint agency agreement with the other agent, and that's what we understood we were entering into. Whether intentionally done or by mistake, the virtual paperwork we signed (yes, lesson learned!) indicated that we had entered into a sole agency agreement with them. This was not mine nor my partner's intention. Parkers did not explain the consequences of this, or the requirement to instruct the other agent to stand down. This may have sounded naive but we are not experts in house selling or contracts! Long story short, we received an offer on the house the following week from a buyer introduced by the first agent. I then received a phone call from Damien, explaining that Parkers were to be due the fees as we had broken the terms of the agreement if this person had been introduced when they had rights as sole agents. I was horrified, stressed and mortified at the prospect of having wasted several thousand pounds. Luckily the buyer was someone who had seen the house several months earlier, but I was frankly shocked at how Parkers then started to treat both me and the other agents. I felt they were aggressive and intimidating, and downright rude. Luckily my first estate agents helped smooth the way and the house successfully sold.