I've had similar mixed experiences of Deliveroo from the Perry Vale. We ordered the fish and chips. The fish was as excellent as ever, but the chips were odd - a huge portion of soggy chips very unlike their normal ones. Which seems odd - wouldn't it be more effort to have different chips for the deliveries?
On another occasion we ordered the calamari and the beet and goat's curd salad for starters. Both excellent and larger portions than in the restaurant. My OH had the burger which he enjoyed. I had the pork belly which was all fat and no meat. But with the most delicious sauce ever.
We ate in the restaurant on New Year's Eve and the food was great. If I order again and get odd chips I'll definitely bring it up with them.