The most probable explanation is that your mobile is infected with malware.
It is not recommended to store more than 'pocket money' on your mobile phone.
A lot of vendors do skip security patches for android (even though showing that the latest patch is installed).
This creates a lot of vulnerabilities which makes it pretty easy for an attacker to infect your mobile.
Do you have any AV software running on your mobile ?
or if is some problem on servers or something
This doesn't look like any kind of server fault. Unfortunately your money is gone.
It is recommended to store
higher amounts either offline or on a hardware wallet.