Hello Jose
zaslal MAHAMAD AMIN SHAIKH v Fórum Saudská Arábia
Not to worrry for this, for your information this is called 90 days temporary stamping which allows you to stay in KSA. Because the Akama stamping takes a time so that is the reason they stamp for 90 days only.
Not to worrry go ahead with it.
Amin Shaikh