Gta V (storyline) I can not buy boiler suit and masks help me

[Kugelschreiber]

I was playing some storyline missions but now I am just stuck .. when I go to buy mask or boiler suit I can not puchase, when I go to boiler setup mission the ammunation is closed and when I go to masks I spam every key but I can not buy them can someone tell me what can I do about it ?