ESA went aboard/coronavirus and return back ESA suspended

Hi

I wanted to query that my mum is claiming ESA and she went aboard at start of march for 4 weeks and I had notified ESA that she will be going aboard and they sent me form to fill to tell them which dates she had gone and I sent it back to ESA but due to the coronavirus she got stuck aboard as the country she visited had gone into lockdown and then her return ticket was cancelled due to lockdown. Which then I notified ESA that she was stranded aboard and they said just tell us when she returns and we will carry on paying her. Once my mum return back to the UK on the special arranged flights by the UK to help british nationals return to UK as that was the only way she could return and she was classed as vulnerable so they prioritize her return. I then rang ESA again and told them that she had return on special UK flight and they ask the date she return which was at end of april which meant she was aboard for a total of 8 weeks but unfortunately the situation cannot be her fault as she couldnt return due to the coronavirus and borders being closed. Then 2 weeks later in may my mum had not received her usual ESA payment so I rang up ESA and they told me that they had suspended her ESA due to being aboard of the 4 weeks that your allowed and the are requesting her passport and they did not notify or write to me to say that they were going to suspend her payments and they want her passport as if I had not phoned I wouldnt not known about they suspending her benefit. Can anyone given any advice and information on what I can do and not allow the ESA to close her claim due to something which was way beyond our control and we cannot be blamed for this.