Hello. I have a TIM SIM card in my phone that I got in Italy. I have data only. There are apps that you can use to hail a taxi, but I cannot use them because you need to be able to receive a text message and I cannot do that as I have data only. Walking to a taxi stand will not always be convenient. I can't make phone calls either. I asked Funk Taxi if I could book using WhatsApp and they said that I have to call. Any suggestions? Thanks.
If the taxi is from your hotel, ask the front desk to do it. If you're out and about, find the nearest hotel and walk up to their taxi stand.
Why don't you use a taxi or rideshare service that has an app that you can use using data? For example, I've used Freenow, Bolt, Uber, and others. I've also heard of itTaxi being used in Italy. The point is that all of these companies have apps, and if you have an app, then you can use data. If you don't want to use up your data, go into a place that has Wi-Fi, like a Starbucks or another coffee shop or hotel room and so on.
ETA: I just realized that you posted this in the Austria Forum. Are you in Austria or are you in Italy? It would help to know what country you're talking about with regards to taxis.