Hello @Chanklish
@Chanklish wrote: There is no vlans or anything
First inaccuracy: in a Switch there is ALWAYS a VLAN defined by default that can not be erased (eventually it can be unused but not erased): the Default VLAN id 1. So, yes, both your two Switches are working by default on all ports untagged members of default VLAN id 1.
@Chanklish wrote: i just want them to act as one switch.
You can't...your two switches will - at best, as you did - be interconnected together through one (if just one port is used) or more physical links (if Trunks - ports aggregations is used)...they can't became a "single logical entity" or a "single switch" (virtual switch) from connected peers' standpoints (no matter if peers are other switches or simple hosts). They simply act as separate switches eventually interconnected (this means that their configurations are separated).
@Chanklish wrote: tried to setup mstp globally but connection was down
If you enabled MSTP as STP mode of operation you need to make sure one of your two switches acts as STP Root (lower priority) and that MSTP configurations are exactly the same (apart from priorities, the MSTP basically requires that instance names, revisions and ids are the same among switches of the same STP domain).
@Chanklish wrote: What should i do ? Stack the two switches
Not necessarily...indeed the stacking feature you're referring to with respect to these two Switch Series could, at best, be the Stacking for Management purposes (using one switch - called the master - to manage others connected to it)...that's not stacking as described above.
I'm not an HPE Employee
Two chained switches with an interconnection made of just one physical link simply can't form a loop...in layman terms: connect A with B...no loop (A-B)...connect A with B then again B to A using an alternate return path...here is the loop (A-B-A).
Are there peraphs two physical links between your two switches instead of just one?
I'm not an HPE Employee