@Sâmia *********
You mean limit of land border entry twice per calendar year, but it's only for 30 days visa exempt entry for specific nationalities. When you are stamped for 90 days, It's based on bilateral agreement, not visa exempt scheme. Some borders would not stamp you in based on those bilateral agreement. That's why
@T**
asks where you are thinking.
And you may not want to go to northern border if you are staying southern Thailand or vice versa. Better mention which area you are thinking if you want to know if it's possible for you to bounce at the border.