Washing machine problem

Hi, I have a question and I will try to make it as short as possible. We had a problem with the washing machine the engineers came ,checked and report it that the heater element needs to be changed . All happy days now ,just to mention the washing machine was not working for 3 weeks and I had to wash all the clothes to the laundrette. They put the order for the heater to come, came to the property and changed it after 2-3 times we used it ,we notice a sound coming from the machine. But to mention that we barely had any clothes left to wash at the time , and this washing machine we used for like 3 years but the machine is 10 years old . Called again the letting agent to call the engineer to see the machine again . They came and said that the drum is bent because we overloaded with clothes . But we didn’t, I spend already alot of money to laundrette. And I received an email from the letting agent saying that we have to replace the washing machine with a new one which is worth 500 £ . I feel that I am being tricked . God know what happed with the machine after the heater was replaced. Any advice ,because I am not paying 500 to buy a new one.

Argos do a decent machine for £200 new