You have a communication problem. Your english is quite iffy, and that will lead to people taking advantage. Your communication must be on point if you want things to go smoothly and to be protected against buyers trying to take advantage.
If you show a basic price of $5 and it accurately describes what you will do for that price, the client can’t complain if they want more for that price and you refuse - Fiverr CS should check the gig and clearly see you are not falsely advertising.
However, if the price shown does not accurately explain exactly what the service is, or it’s written in broken, hard to understand language, the client has a much better chance of having CS side with them.
This will also depend on your gig description. I have a disclaimer on all my gigs saying that the prices shown are ballpark values, and that each project will be priced individually, since what I offer can’t be neatly arranged into set prices, it varies way too much depending on the project. Never had any problems with it, I’m transparent about it. Talk to me, I’ll give you a price. It may be lower than the shown price, or it may be higher, it depends on what the client needs.
Btw, this is part of your bio “if you like my gig press the “ORDER” button for order and share it with your friends and family.” You’re actively telling people to order straight away, without talking to you first. Don’t be surprised if you get a bunch of people ordering the cheapest option, regardless of what they want done.