I can't see what I am doing wrong

You said yourself that you haven't been counting calories or exercising. It's great that you made positive changes to your nutrition, but losing weight takes a calorie deficit, and you don't even know if you are in a deficit without counting calories. Exercise increases that deficit. You need to be doing both.

Hi, thanks for you comment but my nutritionist told me not to count but I can't quite do that yet so whilst not "counting" I am staying within my deficit - 1550 a day which is a 450 daily deficit which should be enough to lose at least a pound a week and whilst exercise helps it is not specifically required to lose weight - lots of people lose weight without doing any exercise at all. I normally exercise every day but life got in the way a bit for the last few weeks. My calorie deficit alone should be making me lose weight not gain it.

I am counting what I eat - my nutritionist told me not to but I can't do that - I have to know - everything I eat is weighed, measured and logged and I am sticking to 1550 a day as per my diary.

Looking at your diary it seems like your weekly intake does not contain more than 300 grams of vegetables. The rest seems to be loads of meat and loafs and even pasta and lentil. These are higher caloric foods and that would be fine if you did some heavier excercise...
I suggest you cook your own meals more using and preparing fresh fish and meat and use vegetables as side dish. (a plate of steamed carrots with right herbs and a spoon of sour cream can be tasty - don't think of it as dull.)
50 grams of baby spinach leaves and 20 grams tomato puree is not really enough for a day of vegetable consumption. Try to up these to be 1/3-d of your daily diet. And I would leave the loaf to max. 2 times a week and also get rid of the T*sco preprocessed whatever.

Hi, I eat veg with most meals - my soup for lunch is full of veg but it is a recipe so you can't see the content but it has celery, carrot, beans and spinach in it- if it definitely more veg than lentil and chicken. I eat at least two meals a week with fish - tuna and haddock and these are also then loaded with vegetables and quinoa. I don't eat pasta much as I am gluten intolerant - i occasionally have GF pasta but not often. The pasta you might be referring to is slim pasta and it is not actually pasta it is made from soluble vegetable fibre and contains next to no cals/carb/sugars

All my meals are prepared from scratch (apart from fish fingers this week) because I have food allergies so I need to know what is in my food otherwise I can have nasty reactions to it I eat bread at weekends but very rarely in the week.. The two occasions that I have eaten bread in the week are both on Weds as I was in a hurry as I had to go to see my nutritionist and there was no time to do anything else.

granted there are some meals where I don't eat a lot of veg but this should not make me gain weight - on the whole I eat healthy self prepared meals - I dont' use fat to cook, I don't eat sweets, I don't use sugar, I very rarely eat highly processed foods, I drink lots of water, I eat three times a day and snack healthily twice a day , i eat a calorie deficit there is no way I should be gaining weight.