Cannot connect to the application server by WIFI, only by Mobile internet

Right now I am in Spain. My Alarm system is installed back home in Belgium cosisting of an Eufy Homebase 2, a panel, 1 movement detector and 4 entry sensors and an indoor camera ( Eufy Indoor Cam 2K Pan & Tilt). With my mobile phone Poco F1 Right now I cannot connect anymore to the app server, while when I switch off WIFI ust using mobile data I can, but switching WIFI back on, I cannot connect anymore. What to do?