Sounds like time for a draft.
Taiwan has a draft.
Wiki
In December 2022, President Tsai Ing-wen announced the extension of compulsory military service to one year from four months from 2024, returning to the duration of conscription from 2008 to 2013, citing the rising military threat from the People’s Liberation Army (PLA) of the People’s Republic of China (PRC).
After completing the service period required by law, the conscription age male citizens are transformed into military reserve force. Male citizens performed Standing Soldier Service has their conscription age end and discharged in the next 1 January after their 36th birthday. However, male citizens performed in Reserved Officer and Non-Commissioned Officer Service has their conscription age end and discharged until they turned 50 in age.