Thanks for that! It seems that the problem is on the network side. The operator hadn’t enabled CA on the closest tower, even though they advertise CA to be available in the area. Trying with a different provider I see CA being activated once there’s some traffic on the line, it isn’t activated by default.
Could you explain how to read the Carrier Aggregation Combination chart? I assume 1 + 8 means bands 1 and 8 combo is supported for CA, but how does the numbers after the “/” change the situation? Is the first number the primary band and numbers after the “+” are possible secondary bands? What about three band CA?