Not Losing Weight

I'm now 5'5 and 150 pounds and about 2 years ago I lost 30 pounds and managed to get down to 120 but unfortunately gained it all back, I wanted a change so I figured I would get back into a healthier lifestyle again, I began my new journey about 2 months ago in May and I cut my daily calorie intake in half and started eating healthy again such as salads, grilled chicken and lots of veggies and made sure my daily intake was around 1,200 calories and also cut out soda. However the entire first month I didn't even manage to lose a pound. Now for the past 3 weeks I've started working out again doing cardio 5 times a week burning 500 calories per day and also doing some resistance training twice a week and sticking to my 1,200 calorie diet as well as drinking at least 112 oz of water per day. However I am still not losing any weight, NOT EVEN 1 POUND. The first time I lost the weight I was doing this exact same routine and it worked perfectly for me, I recently had my thyroid checked and that isn't the problem so I'm not sure what I'm doing wrong, maybe I need to just give it some more time but it's just very frustrating working so hard for 2 months and not seeing any results. It's extremely discouraging. Does any one have any tips or advice?