Well if you are looking for specific advice you'll have to post way more information. Where are you at, how long have you been at a "plateau", what is your calories, how closely do you track them, what is your activity level......etc.
Here's my opinion on this topic.
1. The first solution is patience. We expect our bodies to conform to some mental timetable we cook up, when in reality our bodies are undergoing significant change so plateaus and whooshes are to be expected. Unless you are in a month - 6 week range where you are positive you are in caloric defecit with no change, don't stress.
2. People overestimate their caloric defecit, leading them to believe they are plateauing when they actually are "maintaining". This can happen easily if your defecit is say 300-500 calories a day, but you cheat a couple of times a week. If you do not calorie count, this is a great place to start tackling a plateau, be sure you really are in one
3. If you have been in a true plateau for a while and you are sure you are in defecit, here are some things I have seen around here as options to get going again.
a) Adjust your calories (sometimes down, sometimes up, can't provide tips without knowing a lot more)
b) Zig/zag calories (eat an average amount per week, but vary individual days by 200-400 calories above and below that average)
c) Adjust the content of calories (if you eat a lot of carbs, try reducing this a lot but keeping your calories near the same level)
d) Mix up your exercise, change intensity, time duration, type of workout, all of the above. Sometimes we get in habits in the gym and we start doing the same thing over and over, our bodies get good at it and we don't get the same benefit.
All of that said, to be honest, 8 out of 10 times I see this post on here the answer is either patience (you are looking at too short of a time horizon), or inaccurate calculation of defecit (meaning you "expect" to lose more than you really should).