Too many failures, the latest NVS-O2 failed to enter the designated orbit in February, it was supposed to be the replacement of IRNSS-1E. The available satellites in the constellation are down to just 4, and most of them are older satellites launched in the 2016-2018 timeframe. NVS-01 is the only new one, and is the first satellite with a domestic atomic clock, rest have all imported one's probably nearing their end.Very serious. What happened to domestic atomic clocks?