SRVCC capability and 3G DCR

Hello dears
we face that whenever we set SRVCCcapability to both CS+PS call is being dropped after SRVCC handover from VOLTE to WCDMA after 11 seconds, we changed it to CS only and issue is solved but PS reestablishment is taking time now, our radio is E/// and core is huawei, all RAB combinations are active in RNC side, do u have any idea what could be the reason ?