AT1 should start with a zero ohm resistor. AT2 should start with a 1.8nH inductor. In order to start tuning the antenna a coax cable should be placed at the GNSS pin at the SIM7070 module. The antenna should be placed in the plastic housing before adjusting the matching components on AT1 and AT2. The tuning should be optimized until the band edges meet -10dB return loss (2:1 VSWR).
Also, on the trace from RFO to the GNSS pin there should be a series 22pF capacitor and a 47nH on the VCC supply to the M20057. These components should be in place when you start tuning the antenna.