Nonsensical service and special!!!

I spent almost 15 minutes without being attended to and I wasn’t made aware that there was a shortage of staff whatsoever. I ordered the burger and chips with milkshake special and my burger and chips were brought in a hot plate suggesting that they were heated with microwave, the chips weren’t even crispy as usual. The milkshake was brought later due to machine that was stuck it was watery with no marshmallows. Who was the special made for before it was heated for me? I almost left without paying because I wasn’t attended to I ended up paying at the till, I’m really disappointed, I wasted my money…..