Wait another 24 hours, the delay may be caused by a technical complication or the waiting line of taken tests is too long. Stay in isolation during that time. If you still do not receive the information about the result after 48 hours (at least in text message), call the facility where you got tested. Your contact form might have had the wrong contact details. You can find a list of contacts on the website of UZIS.
You can also call the line 1221, where they can look into the testing system. But keep in mind that the 1221 line operators are not doctors or paramedics. Therefore, according to the law, they cannot tell you if your test is positive (give you a diagnosis), they can only tell you if it's negative. In the case of positivity, they can only tell you that they see the result, but they cannot tell you. This more or less means that you are positive and it is already an information that you can work with. Do not call the hygiene station, as the personnel there cannot help you with that matter.