Ryanair complaint: Admin Charge Not Applicable

I booked a flight to Faro on 2672020 reference LB6STN to fly on 14th – 26th August costing £283.08. On 9th August 2020 I changed the flight to fly on the 22nd – 30th August costing another £141.10, I was charged admin fee even though I thought at the time it should have been free but, when I read the small print I realised you need to do 7 days before you fly.

On Friday 14th August I tried to change my flight as it is apparent that there is not going to be an air bridge put in place and both my friend and I can not quarantine as work will not allow but it was trying to charge me another £180 so saturday morning I tried to call unsuccessfully, I eventually managed to communicate online but was just told I would have to pay another admin fee. I am willing to rebook this flight but not pay another admin fee. Can you please advise why I was not able to rebook on Friday without admin fee on Friday night. I am going to lose this money.